Abstract: A pet food, such as a dog food and a cat food, contains a cyclodextrin such as &bgr;-cyclodextrin, for example, a pet food in which the content of fat is equal to or higher than 5% by weight per solid part and the content of &bgr;-cyclodextrin ranges from 1 to 15% by weight per solid part. A method of suppressing an increase in the body weight of a pet or reducing the body weight, is characterized by feeding the pet food to a pet to the extent that the ingested amount of &bgr;-cyclodextrin, per day, ranges from 0.1 to 5 g per 1 kg of body weight. A pet food is suited to a pet's liking because of having the same taste and mouth feel as conventional pet foods, and suppresses an increase in the body weight of a pet or reduces body weight with the same feeding amount as usual, and a method suppresses an increase in the body weight of a pet or reduces body weight without impairing the health of pets.