Nontyphoidal salmonellosis has a wide variety of clinical presentations. With the aim of describing the detailed clinical presentations of gastroenteritis caused by nontyphoidal Salmonella spp., findings for 126 patients (1-94 years of age; 37.0 years on average) were analyzed. Nontyphoidal salmonellosis is prevalent from April to October in Akita, when the mean atmospheric temperature exceeds 10 degrees C. On physical examination, 3 patients had rebound tenderness and muscle guarding on their abdominal wall; 1 of these patients underwent surgery for associated acute appendicitis. Elderly patients tended to be more seriously affected, resulting in severe dehydration. Elevation of the serum C-reactive protein (CRP) level correlated well with a decline in the platelet count. Although nontyphoidal salmonellosis is a common cause of acute gastroenteritis, thorough investigation and meticulous care are required so that conditions requiring surgical treatment or those that are potentially fatal are not overlooked.