Is your Chihuahua barking at night for no reason? Here are some reasons why and what you can do to help. 1. Loneliness: Chihuahuas may bark if they feel lonely or have separation anxiety. Try letting them sleep in your bedroom for comfort. 2. Nighttime Anxiety: Fear of the dark or unknown sounds may cause barking. Setting up outdoor cameras can help identify the cause. 3. Boredom: A lack of exercise during the day could lead to nighttime barking. Take your Chihuahua for a walk to burn off energy. 4. Medical Conditions: Health issues like dementia or pain could be causing the barking. A vet visit may be necessary. 5. Need to Pee: Younger Chihuahuas may bark at night if they need to go outside to pee.