Have you been feeding your dog, cat or rabbit too many treats, leftovers or special snacks?
The pet charity PDSA says there's a big increase in fat pets.
It says it has diagnosed many more animals as clinically obese in the last two years.
Being overweight can cause health problems for animals.
It can lead to heart disease, cancer, diabetes and arthritis.
The charity's now running a six week Pet Fit Club to help animals lose weight and fat and teach owners how to feed their pets more healthily.