Anna studied psychology, law, English, and animal welfare in college. She is
a mother of two and a 2019 bride!
This article will break down 15 of the most aggressive dog breeds around the
world and give you a few details about each one.
skeeze, CC0, via Pixabay
What Makes Dogs Vicious?
What makes a dog aggressive is highly disputed amongst dog owners and
breeders. While many people insist that even the most ‘dangerous’ breeds can
make excellent family pets with the right amount of socialization and proper,
firm training, others believe that certain breeds of dog are more high risk
than others due to their breeding history.
Many dogs like the German Shepherd, for example, have been bred largely to
guard and protect their families. This means that while they can make
fantastic family pets and are usually safe around the family’s children, they
can be overprotective, which can result in injuries to strangers.
This article will break down some of the most aggressive dog breeds in the
world so that you can make a more informed call about which canine to
introduce into your family.
The Top 15 Most Aggressive Dog Breeds
- Presa Canario or Canarian Catch Dog
- Tosa Inu
- Neapolitan Mastiff
- Gull Dong or Pakistani Bulldog
- Pit Bull Terrier
- Caucasian Shepherd or Caucasian Ovcharka
- Rhodesian Ridgeback
- Saint Bernard
- Dogo Argentino
- German Shepherd
- Chow Chow
Dogs Bred for Fighting
The Presa Canario was originally bred for dogfighting rings.
1. Presa Canario or Canarian Catch Dog
The Presa Canario is a massive breed of fighting dog, which has been known to
attack and kill humans. They were bred originally for an Aryan Brotherhood
dogfighting ring, but they have also been used for guarding livestock.
Also known as a ‘Canarian Catch Dog’, this breed requires very early
socialisation and obedience training. If they have not been with a very
experienced owner, they can be a danger to people and other animals.
The Tosa Inu can weigh up to 130–200 lbs and has been banned in many
2. Tosa Inu
The Tosa Inu is one of the world’s most dangerous dogs. This massive breed can
typically weigh anywhere between 130–200 lbs and stands around 32 inches tall.
It is legally banned in many countries due to the aggressive nature of the
breed. It originated in Japan, where it was bred to be a powerful, muscular
dog for fighting other dogs. Even the best-trained dogs of this breed could
become overprotective and attack humans.
The Neapolitan Mastiff was once used as a gladiator dog and has been banned in
3. Neapolitan Mastiff
The Neapolitan Mastiff is famous for the role of Hagrid’s pet dog, Fang, in
the Harry Potter films. Although in those particular films, Fang is a
docile, lazy creature, in reality, these dogs are banned in many different
They have been used as war dogs by the Roman legions and also as gladiator
dogs in the bloody ‘sport’ within the colosseum in Italy, where the breed
originated. Males can top 200 lbs and can be strong, willful and vicious.
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The Gull Dong can be extremely aggressive, defiant, difficult to control and
4. Gull Dong or Pakistani Bulldog
The Gull Dong is another breed that, sadly, was specifically developed as a
fighting dog. It is also known as the Pakistani Bulldog and is the result of a
Bully Kutta crossed with a Gull Terrier.
This dog is extremely aggressive and made even more dangerous by the fact it
can be defiant, difficult to control, incredibly powerful, muscular and
athletic. This breed should never be kept by any person who is not an expert
in dog training. If they are not trained properly and socialised from a very
early age, they can turn aggressive towards people and other dogs.
The Pit Bull Terrier is known around the world as perhaps the most powerful
pound-for-pound lean muscle fighting dog on the planet.
5. Pit Bull Terriers
Pit Bull Terriers have been selectively bred from a range of other terrier
breeds and bulldogs in order to create a dog breed that was second to none in
dog fights. The people who set out to do this succeeded—this dog holds the No.
1 rank for pound-to-pound lean muscle tissue.
Although this breed is capable of being a loyal, friendly pet and excellent
guard dog, it has also attracted the wrong kind of attention from around 1980,
when these dogs were bought by many criminals and people involved in
dogfighting rings as a statement of masculinity. Aggressive dogs were bred and
encouraged to be aggressive towards other canines in order to be excellent
fighters. As a result, many once friendly, sweet-natured breeds are now
illegal in many countries and American states.
They also have an extremely high prey drive that is triggered by smaller
mammals, meaning families with smaller children would likely be unwise to own
this dog. Many bites have resulted in fatalities to both adults and children
Dogs Bred for Hunting and Gathering
The Caucasian Shepherd is highly territorial and prone to attacking strangers.
6. Caucasian Shepherd or Caucasian Ovcharka
The Caucasian Shepherd, also known as the Caucasian Ovcharka, was bred for the
purpose of guarding homes and livestock. It is a courageous and strong-willed
breed, which can make training problematic.
It is also prone to attacking strangers due to the fact that it is highly
territorial. It is fearless, dominant and powerful, which makes dogs of this
breed very dangerous if they are not well trained.
Males weigh at least 110 lbs and stand around 30 inches tall. Even though many
families insist that this dog can be good with children, it is strongly
recommended the two are not left alone, as accidental injury can easily occur.
The Rhodesian Ridgeback can be overprotective and was once used to protect its
masters from lions.
7. Rhodesian Ridgeback
The Rhodesian Ridgeback is renowned for being used to keep lions away from its
master and to keep prey subdued while its owner hunted game. This dog makes an
incredibly loyal companion if it is well-trained.
If it is not kept by an experienced dog owner who does not spend almost all
their time with the dog, this breed is known for becoming dominant and can be
prone to developing a highly aggressive side with other dogs and also people.
Saint Bernards can be very stubborn, difficult to train and require very early
8. Saint Bernard
The Saint Bernard is another huge breed of working dog, which originally was
bred in the Italian Alps. Although they are portrayed in many films and
photographs as giant teddy bears, in reality, they are very stubborn,
difficult to train and require very early socialisation.
Saint Bernards are renowned, however, for rescuing people who have become lost
in mountainous areas.
The Basenji can become aggressive towards other dogs and strangers and is
exceedingly difficult to train.
The Basenji is a beautiful breed of dog and has been classified as a
sighthound for its incredible intelligence, constant alert state and loyalty.
They are also known as the second most difficult breed to train, however, and
can become aggressive towards other dogs and strangers if they are not
The Dogo Argentino was originially bred for hunting large game, such as wild
boar and pumas, and is illegal to own in the United Kingdom.
10. Dogo Argentino
The Dogo Argentino was originally bred for hunting large game such as wild
boar and pumas. It is illegal to own this breed in the United Kingdom under
the Dangerous Dogs Act 1991, due to a number of attacks.
Whilst it is friendly, loyal and affectionate towards its owner, this breed is
fiercely protective and will not hesitate to turn on strangers if it believes
they are a threat.
It is extremely territorial, making it an excellent guard dog. But it can also
be vicious, as stated previously, and will instantly defend its territory and
family against intruders.
The Boerboel’s loyalty to its family can make it vicious towards strangers and
947051, CC0, via Pixabay
The Boerboel is a large mastiff breed originating from South Africa, which was
selectively bred for the purpose of being a guard dog. Like the Dogo
Argentino, its loyalty to its family can make it vicious towards strangers and
German Shepherds have been known to bite humans who have been thought of as
threatening to their ‘pack’ or individuals who have ‘intruded’.
12. German Shepherd
German Shepherds, as the name suggests, originally came from Germany and are
very popular as pets and also police dogs. They were bred to be superb guard
dogs and fill this role very well due to their territorial nature.
They are known to become overprotective, however. This breed has been known to
bite humans who have been thought of as threatening to their ‘pack’ or
individuals who have ‘intruded’.
Rottweilers can be overprotective of their family and home and also have a
high prey drive.
Rottweilers have also been bred to be heavy-duty guard dogs and can be very
good as such. Unfortunately, Rottweilers have earned a bad reputation due to a
fair number of attacks on both people and other animals, including livestock
such as sheep, which have died as a result.
Many individuals say these instances occurred due to poor training and a lack
of socialisation. But it is generally agreed that this breed is prone to
developing a vicious streak if managed incorrectly, can be overprotective of
its family and home and also has a high prey drive—more than a handful of
Rottweiler attacks have happened recently involving toddlers.
Boxers can be boisterous, dominant, aggressive and overly protective of their
From 1982 to 2012, there were at least 48 instances reported of Boxer dogs
causing significant injury to humans. They can be wonderful family pets if
their owner has had previous dog handling experience and is able to dedicate
time and effort to training. But without this, they can be boisterous,
dominant and aggressive, meaning they can be a danger to people.
This breed is known to be extremely affectionate towards the family it lives
with, and seeing this well-loved breed on a list with other dangerous breeds
may come as a shock. But it is not recommended to pick this dog breed if you
have never owned a dog before.
The Chow Chow is known to be fiercely protective of its owner.
15. Chow Chow
The Chow Chow, affectionately known as the ‘fluffy lion dog’, originated in
China and is considered high risk as a breed. There have been 238 fatalities
from dog bites from 1979 to 1998 due to this breed being so fiercely
protective of its owner.
It is also a large, heavy breed, meaning that it can be a danger to small
children, even when it is only playing.
Let me know what you think!
Ivan on July 30, 2020:
Humans are to blame for bad behaviour of dogs. I have Loved and Owned numerous
Bullterriers and Pitbull Terriers. They were gentle, caring, loveable and most
importantly fantastic around Kids.There is a saying that a dog is an identocal
blueprint of its owners personality. Painfully dogs go to the wrong homes for
the wrong reasons.
Anonymous on July 16, 2020:
I agree dogs are never born aggressive they only ever become that because of
people who breed them for the wrong reasons and never treat them right
I love dogs on June 11, 2020:
I don’t think the Basjeni is that mean.
Dog lover 123 on April 13, 2020:
Yep dogs are never aggressive born it is the people who train them to do bad
and then wonder when people get attacked. This is stereotyping to dogs
Melina on December 21, 2019:
Dogs are not aggressive, they are aggressive because of their owners on how
the treat them or train them too. So don’t be hating on dogs please.
Sophie on June 18, 2019:
IVE ALWAYS WANTED A DOBERMAN
Nanette Hazelton on May 01, 2019:
Ive owned 4 rescue dobermans. All were velcro dogs with family. Very loving
and cuddlers. But, if anyone not known to my family dares step on my property
they become very loyal guard dogs. Fear noone. Love the breed which is why i
always rescue a dobie.
Sarah on March 21, 2019:
If ur not willing to trust ur dog alone with ur kids dont own a dog period.
Having a pet is about trust and love. If u trust each other and love each
other then u have nothing to worry about. Also u shouldnt be an aspiring vet.
A dog u dont know i agree but if its ur dog it should be part of the family
and is more prone to protect its family then to attack it. Its really sad to
see miss informed articles like this floating around. I hope actually believes
Hannah on December 19, 2018:
I must admit I laughed at this ill informed article. Your headline photo is a
Dobermann, but you don’t even list them, and rightly so. Any dog is a danger
if not properly trained, and no dog should ever be left alone with children,
no matter how well trained they are. All breeds were bred initially for one
purpose, but over time the requirement for them has lessened and are now
usually owned as pets or for showing. The author of this piece is clearly not
very knowledgable in dogs or in dog husbandry so shouldn’t be writing such
Molossus of Epirus on August 26, 2018:
As soon as I saw, “They were bred originally for an Aryan Brotherhood dog
fighting ring, but have also been used for guarding livestock.”, said of the
presa canario I knew that you didn’t know what you were talking about.
The Perro de Presa Canario has been used as a working dog since the 16th
century in their native Canary Islands, and ceremonial use possibly predates
that. Fights did happen, but this wasnt the purpose of the dog, and it is
inferior to other dogs for this purpose as you can’t handle it in the pit
(unlike American Pitbull Terriers).
Next time you want to write this sensationalist crap, do the proper research.
I didnt read the rest of the article, you lost me at the presa, but I wouldn’t
be surprised if it contained more of the same catchpenny nonsense.
Davi on June 17, 2017:
Dogs in some of the pictures were not the dogs they were describing,also pits
are good with children.don’t think the author know much about dog breeds
Crystal Galvan-Casas on February 15, 2017:
I bred Chow Chows. Mine were bred and trained with love. The only ones that
were in danger were people that had no business or permission to be in or at
our home. Raised 2 girls with them and the chows were very protective of them.
Chows were initially bred for the Chinese royalty, hence the name. Bred to
protect one person which is what they do. With love they are great pets.
Robert on December 30, 2016:
At guarding doga you forgot dobermann
Val on October 22, 2016:
I’m more afraid of an ankle biting chihuahua, than I am of a pit bull. Evil
dog fighters & animal abusers in general, should take the “most vicious” spot
in place of pits.
Faye on September 05, 2016:
The Caucasian ovcharka on this article is in fact a Photo of a TIBETAN
Ida on June 17, 2016:
I agree St. Bernards can be a hassle to train, but I personally have dog sat a
lost of them. They get right up in your face, and lick you all over. This
breed, in my opinion, isn’t a first choice for first time owners, though I
must say they are very affectionate large beasties.
Pepper on January 07, 2015:
You’ve hit the ball out the park! Inerldibec!
Tolovaj Publishing House from Ljubljana on August 03, 2014:
Every breed was raised for certain purpose. If they stay under control, I
don’t have a problem with aggressive breeds.
ohcaroline on June 07, 2014:
I’ve never been fond of large dogs mean or otherwise. I don’t like to be
around them when they are aggressive. My next door neighbor has a large mixed
breed dog and when she takes it out to walk it…I stay indoors because it
will get aggressive and we share the same carport. I don’t try to get in my
car when she has it out.
Lorna from USA on May 12, 2014:
I learned a lot about dogs today, I never thought that Saint Bernard could
become aggressive if not trained properly. Thanks!
VioletteRose LM on May 05, 2014:
Great lens! I love dogs, so this information is really important. Thanks for
Anna (author) from chichester on May 01, 2014:
Wow KonaGirl that’s fascinating! They sound like incredibly vicious dogs… I
definitely wouldn’t want to be the boar! Thank you for letting me know about
the Aryan Brotherhood too – I must have mis-read something while researching
for this article, I will double-check and correct that mistake!
KonaGirl from New York on May 01, 2014:
Some of these breeds I had never heard of so found this article very
interesting. I have to disagree with you about the Aryan Brotherhood
originally breeding the Presa Canario. This Spanish dog breed is much older
than the existence of the prison gang. In Hawaii, my relatives cross bred Pit
Bulls and Bull Terriers for a special bred to hunt wild boar. Very dangerous
dogs and now a common breed in the islands. They have the stature and strength
of the pit bull with the ability to lock their massive bull terrier jaws on
the pig and anyone else that gets in their way.
Anna (author) from chichester on April 30, 2014:
That’s so true Janis – pit bulls really can be lovely, but they just seem to
be one breed that’s become a ‘status’ dog with people who have mo idea about
training or handling.very sad, as many animals then have to be destroyed
because they weren’t provided with proper care and attention.
WriterJanis2 on April 30, 2014:
We used to have a pitbull. We adopted her as an older dog. She was the most
gentile dog I have ever known and was wonderful with our children. It’s sad
when some pet owners try to make their dogs so mean, when they can be so kind.
Miha Gasper from Ljubljana, Slovenia, EU on April 27, 2014:
It’s very interesting to see how different can be breeds. I believe owners of
most aggressive breeds should possess some kind of certificate proving they
can handle them. I also think some breeds are simply not suitable for city
areas with a lot of people and not enough space for running. It’s just not
fair to dogs and can be dangerous for dogs and people.
Anna (author) from chichester on April 18, 2014:
@BLouw: How awful for the family! I agree though – no dog is truly safe, I
would never leave my child alone with one no matter how big, small, laid back
etc. You never know and it just isn’t worth the risk
Barbara Walton from France on April 18, 2014:
I remember as a child neighbours had two Chow Chows and they attacked their
little girl and bit all the way up her arms. I’d always be safe and choose a
real family breed of dog and never trust a dog with a young child.