The ketogenic diet, a high-fat diet, is a therapeutic alternative in the treatment of refractory epilepsy, especially in children. However, there are concerns that a high-fat diet may influence the normal development of the central nervous system and cognition. In this study we investigated the influence of ketogenic diet on adult neurogenesis in the dentate gyrus. Rats were provided with either a high-fat diet (80% fat) or a standard rat diet (5% fat) ad libitum for 4 weeks. In both female and male rats, the amounts of bromodeoxyuridine immunoreactive cells in the dentate gyrus were the same in the different groups. Our results suggest that the ketogenic diet does not disturb the neurogenesis in the rat dentate gyrus.