Is My Shih Tzu Aggressive? Biting, Growling, and What to Do

How we researched this article: This guide follows the American Veterinary Medical Association (AVMA) on dog bites, the American Veterinary Society of Animal Behavior (AVSAB) on training, the American Kennel Club (AKC) breed standard, and veterinary health information from the AKC Canine Health Foundation and Cornell University. Every source is listed at the end. Last reviewed: September 2026.

If your dog has bitten someone: wash the wound with soap and water and seek medical care for anything more than a minor scratch. Keep your dog separated and calm, confirm its rabies vaccination is current, and follow your local reporting rules. Then book a vet visit to look for pain or illness.

The Short Answer

Shih Tzus are not a mean or aggressive breed. The AKC breed standard describes the ideal Shih Tzu temperament as outgoing, happy, affectionate, friendly, and trusting toward all.

But any dog can bite. The AVMA says it is not a dog’s breed that determines whether it will bite, but the dog’s individual history and behavior. When a Shih Tzu growls, snaps, or bites, there is almost always a reason, such as pain, fear, or protecting something it values.

Why Do People Call Shih Tzus “Mean” or “the Worst Dogs”?

Usually because of a bad experience with one dog. Small dogs are sometimes handled roughly, picked up without warning, or never taught what to do instead of snapping. The AVMA considers it inappropriate to label specific breeds as aggressive or dangerous, and says any dog can bite depending on the situation.

Common Causes of Aggression in Shih Tzus

Pain

The AVMA notes that dogs in pain are more likely to bite. For Shih Tzus, two common sources of pain are worth checking:

• Spinal pain. The AKC Canine Health Foundation lists Shih Tzus among the breeds most commonly affected by intervertebral disc disease (IVDD). Cornell University lists unusual aggression when touched, crying out when moving, and reluctance to be lifted among its signs.
• Dental pain. Dental disease is the most common health problem in Shih Tzus. A sore mouth can make a dog snap when its face is touched.

Fear

A frightened dog may growl or bite to make something scary go away. Common triggers include strangers, children, other dogs, grooming, and vet visits.

Resource guarding

Some dogs protect food, toys, beds, or even a person. Signs include freezing, growling, or eating faster when someone comes near.

Handling sensitivity

Many Shih Tzus dislike having their face, paws, or eyes handled, which Shih Tzu grooming requires often. This is often fear that can be improved with slow, rewarding practice.

Learn the Warning Signs

Dogs usually warn before they bite. The AVMA advises learning the signs that your dog is stressed or uncomfortable and removing it from the situation. Watch for:

• Licking lips, yawning, or turning the head away
• Showing the whites of the eyes
• Freezing or going stiff
• Growling or lifting a lip
• Snapping in the air

Never punish a growl. The AVSAB warns that punishment can suppress a dog’s warning signs without changing the fear behind them. A dog that learns not to growl may bite later with less warning.

Puppy Nipping Is Different

Puppies explore with their mouths and nip during play. This is normal, not aggression. To teach gentle play:

• Redirect nipping onto a chew toy.
• If your puppy nips skin, calmly pause play for a few seconds.
• Give plenty of chew toys, especially while teething.
• Never hit, flick, or hold the mouth shut.

How to Help an Aggressive Shih Tzu

• Start with a vet visit to look for pain or illness.
• Avoid the triggers for now. Prevention keeps everyone safe while you work on the problem.
• Use reward-based training. The AVSAB recommends only reward-based methods for all dog training, including behavior problems. It advises against shock collars, prong collars, choke chains, and leash corrections.
• Build positive associations with handling, grooming, and visitors, in small steps paired with treats.
• Get professional help for any bite or growing aggression. Ask your vet about a board-certified veterinary behaviorist or a certified trainer who uses humane methods. Some dogs also benefit from medication prescribed by a vet.

Keep Children and Visitors Safe

• Supervise all interactions between dogs and young children.
• Teach children not to hug, kiss, or pick up the dog, and to leave it alone while eating or sleeping.
• Give your dog a quiet place to retreat to.

How Strong Is a Shih Tzu Bite?

We could not find a published, measured bite force for Shih Tzus. Numbers you may see online are not backed by research. What matters more is that even a small dog’s bite can injure, especially a child’s face or hands.

Should a Shih Tzu Wear a Muzzle?

A muzzle can be a useful safety tool for vet visits or grooming if your dog may bite. It is not a way to stop barking or a substitute for training. Flat-faced breeds like the Shih Tzu need a muzzle designed for short noses that lets them pant and drink. Introduce it slowly with treats, and never leave a muzzled dog unsupervised or in the heat.

Related: barking, screaming, and howling and Shih Tzu teeth care.

Frequently Asked Questions

Sources

• American Veterinary Medical Association. Preventing Dog Bites.
• American Veterinary Medical Association. Dog Bite Prevention Policy.
• American Veterinary Society of Animal Behavior. Position Statements.
• Humane Society of Missouri. AVSAB Position Statement on the Use of Punishment.
• American Kennel Club. Official Standard of the Shih Tzu.
• AKC Canine Health Foundation. Overview of Intervertebral Disc Disease.
• Cornell University Riney Canine Health Center. Chondrodystrophy and Intervertebral Disc Disease.

This article is for general information. It is not a substitute for advice from your veterinarian or a qualified behavior professional. Read our medical disclaimer.