Are Neapolitan Mastiffs
Aggressive or Dangerous?

by Ken Alden


If you’re interested in a Neapolitan Mastiff, you should learn as much as you can about the breed. That way, you can make sure it’s the dog breed for you. They can be great for some people, but they aren’t the best for everyone.

Are Neapolitan Mastiffs Aggressive Or Dangerous?

As a general rule Neapolitan Mastiffs can be aggressive when they don’t have early socialization. Their size alone can also make them dangerous, especially around small children. They can also be aggressive when they sense a threat toward themselves or their family. But it is possible to reduce those tendencies.

Whether you’ve had dogs before or not, you should consider if Neapolitan Mastiffs are the right breed for you. They can make a great pet, but they require a lot of socialization and training. Keep reading to learn how their aggressiveness can affect them and you. Read More Below...

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Are Neapolitan Mastiffs aggressive or dangerous?


Are Neapolitan Mastiffs Aggressive Toward People?

Neapolitan Mastiffs can be aggressive toward strangers, especially when the dog senses a threat. They’re very protective and loyal to their owners, so the dog will do what it can to protect you. 

On the one hand, this can save you from an attack. However, it can be a problem if you have visitors or meet other people with your dog in public. If your dog doesn’t recognize the other person, they may try to attack.

When having your dog meet a new person, make sure the person stays calm. That way, the dog can know the person isn’t a threat, and they won’t lash out. The more your dog meets a person, the more comfortable they will get.

Are Neapolitan Mastiffs Aggressive Toward Other Dogs?

When asking are Neapolitan Mastiffs aggressive or dangerous it's important to know that this breed can be aggressive toward other dogs. The problem is especially common in dogs of the same sex. A Neapolitan Mastiff wants to be the boss, and their size makes it easy for them to take control.

If you want to have a Neapolitan Mastiff with another dog, you should consider the sex. That way, you can make sure the dogs can live together.

But if you want two dogs of the same sex, you can make it work with socialization and training. If you already have the Mastiff, take them to the dog park to meet other dogs. Then, when you bring home a second dog, they can interact and know that other dogs are okay.

Learn More...
Our article about the temperament of the Neapolitan Mastiff will help further explain why they behave as they do.

Pro-tip: Neapolitan Mastiff anxiety, aggression, destructive chewing, jumping up, fearfulness, and other behaviors can be controlled with the right training program.

Here’s a great course that addresses these issues along with many other dog training basics: Check it out now!

Are Neapolitan Mastiffs Aggressive Toward Other Pets?

Perhaps you love more than just dogs, so you also have or want a cat. Because cats can run, that can make a Mastiff want to run after the cat. Neapolitan Mastiffs have predatory instincts that can come out when they see a cat or another small animal run.

While running isn’t aggressive in and of itself, it can be dangerous for the other pet. Neapolitan Mastiffs are large, especially as adults. Compare that size to the average cat, and the dog could hurt your other pet.

You can have a Neapolitan Mastiff and another pet, but you should be careful. Make sure the smaller pet has a safe space with food and water. In the case of a cat, make sure they also have a litter box that they can use and that they can get to it and away from your Mastiff. 

Are Neapolitan Mastiffs Dangerous?

Neapolitan Mastiffs can be dangerous, even if they aren’t being aggressive. The breed can reach 24 to 31 inches (60.96 to 78.74 cm) tall as an adult, depending on the sex. They can weigh anywhere from 110 to 150 pounds (50 to 68 kg), also depending on the gender. 

Their size alone can make them dangerous around babies and young kids. When the kid is smaller than the dog, it can be easy for the dog to hurt the child without meaning to.

The dog can also break certain things around your house if they knock them off a table while walking by. You could have the calmest Neapolitan Mastiff, but that doesn’t totally negate the risks of them hurting you or someone else.

Pro-tip: Neopolitan Mastiff's (and their owners) love dog crates…and for good reasons. Crates keep dogs from mischief while you're away, are perfect for house training, for traveling by car, and provide the dog a place to de-stress. Check out the best Mastiff crates on Amazon.com now.

How To Avoid Aggression in Neapolitan Mastiffs

If you want to get a Neapolitan Mastiff, you can avoid the breed’s aggressive nature. It can take a lot of work to train your dog to be calm and easygoing, but it can be worth it.

Whether you have kids, other pets, or not, you should train your dog not to be aggressive. That way, you won’t have to worry about having visitors over or worry about having kids or pets in the future. 

Consider a few things you can do to avoid or at least lower the risk of aggression in your Neapolitan Mastiff. 

Socializing Your Neapolitan Mastiff Early

As soon as you get a Neapolitan Mastiff, you should expose the dog to people and other animals. Take your dog to a dog park or a regular park to see others. Have people with or without pets visit you at home.

Visits from family and close friends are super important because you don’t want your dog to attack them. If you can have visitors over soon after you get your dog, they can start to get to know those other people and not sense them as a threat.

If you have another pet already, keep them away from the Neapolitan Mastiff but introduce them in small bursts. Give the smaller pet a place where they can go to be away from the dog. Then, your other pet can feel safe, and your Neapolitan Mastiff can meet the other pet slowly. are neapolitan mastiffs aggressive or dangerous

Learn More...
Here's a helpful article of ours that gives some great tips on some creative ways to socialize your pooch.

Giving Your Neo Positive Reinforcement

You may also need to spend a lot of time training your Neapolitan Mastiff. Give them treats for positive reinforcement when your dog doesn’t get aggressive. However, avoid using negative reinforcement because the Mastiff may not respond as well.

If they act aggressive, be stern until they calm down and give them a treat when they do get calm. Make sure they get and stay calm for a few seconds. That will teach your dog not to act out around certain people or animals.

You may need to reinforce good habits long after you start training your dog. Being consistent will also help teach your dog how they should act.

Enough Exercise Is Important

It can also help for your dog to get enough physical activity. Give your dog some time to play and run around so that they get their energy out in a healthy way.

That way, they won’t be as tempted to get physically aggressive with people or pets. This can help a lot if you have a cat or small dog that likes to run from your Mastiff. If the Mastiff is tired, they may not run after the other pet as quickly.

While you can’t always take your dog on walks, they should get some exercise each day. Not only will that help with aggression, but it can help keep your dog healthy.

Learn More...
How much exercise is enough for your Neo? Can you exercise them too much?
Learn this and more from our article about Mastiff exercise.

Ongoing Training For Your Dog

While you should train your dog when you first bring them home, the training shouldn’t stop. Keep up with the positive reinforcement as your dog grows and reaches adulthood. Make sure your dog continues to understand how they should act.

If you have others in your family training the dog, you should all follow the same training methods. Then, you can keep everything consistent for your dog to avoid confusion. 

Use the same commands and treats. Try to also use the same tone when training the dog so that they can understand positive reinforcement vs. you being stern when they do something bad.


Are Neapolitan Mastiffs Aggressive Or Dangerous?...Final Thoughts

Neapolitan Mastiffs can be aggressive, and their size makes them dangerous if they aren’t careful. However, you can use socialization and training to help. That way, your dog can be calm while also being loyal and protective.


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About Author


About the Author...

Ken Alden, a dedicated Mastiff owner for over eight years, is acclaimed for his expertise in care, grooming, and training. Read more About Me and my dog Shadow.

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