A case of enetritis caused by Clostridium perfringens was observed in 4years old, male California sea lion(Zalophus californianus). Clinical signs were included in anorexia, depression, diarrhea and vomitting, and the animal died on 4 days after showing clinical signs. Grossly, bloody contents were presented in the intestine and the intestinal mucosa were congested and dark redcolored, and also there were serous fluid in the peritoneal cavity. Histopathologically coagulative necrosis destroyed two third of the villus. Clostridium perfringens were isolated from the intestinal contents. Based on the gross and histopathological findings, this case was diagnosed as necrotic enteritis caused by Clostridium perfringens infection.