Understanding your Chihuahua’s behavior

Dogs 2 min read Updated on October 6, 2026

In shortThe Chihuahua lives in a world of giants. Much of what gets called “bad temper” is alert or fear, and size makes neither less real.

What defines them

The smallest of dogs has the brain of a full dog: he guards, he alerts, he bonds intensely to one or two people. Carried, set on laps, often protected by reflex, he frequently lacks chances to learn to handle the world himself. The result: he barks from a distance and bares his teeth when cornered, because fleeing at that size is hard. His language is the same as a large dog’s, only faster.

What matters when you read them

He barks when someone comes in: alert, not aggression. He signals; check and reassure.
He freezes and bares his teeth when a hand reaches out: fear. He cannot flee, so he warns. Step back.
He trembles: cold, excitement or stress. Context decides, and cold is real for him.
He refuses to leave your arms: he feels stronger there. Teach him the floor gently.

Three things that help

A high spot of his own. A cushion on the sofa, a view of the room. He watches to reassure himself: give him a post that is not your arms.

Protection from feet and hands. A place where nobody scoops him up when the bell rings. Visitors do not pick him up without his consent.

Chosen encounters. Calm dogs, at his pace, on the ground. No crowded park. He learns the world is manageable.

Young, adult, senior

As a puppy he is so small you carry him everywhere: let him walk and explore, that is where his confidence is built. As an adult he needs real walks, not a lap around in your arms. As a senior, watch the teeth (very exposed), heart and knees. A Chihuahua who no longer jumps on the sofa or chews on one side is talking about pain.

Frequently asked questions

My Chihuahua bites visitors who want to pet him. What can I do?

He has not learned that unfamiliar hands are safe, and nobody asked his opinion. Simple rule: visitors ignore him, do not pick him up, toss a treat on the floor. He comes if he wants. A behaviorist can speed things up if the fear is strong.

He growls at my partner when he is on my lap. Is he jealous?

He is guarding a resource, you, from a high position that makes him feel safer. Have him get down calmly when it happens, and teach him that the approaching partner brings good things. Do not let him run your lap like territory.

My Chihuahua trembles a lot. Is he scared of everything?

Not necessarily. At his size, cold is real from 60°F, and excitement makes him tremble too. Look at the rest: flattened ears and tucked tail mean fear; loose body and wagging tail mean excitement. A sweater in winter is not a whim.

Mimo reads behavior. It does not replace a vet.