Abstract: Objective To analyze the epidemiological characteristics of infectious diarrhea in Ninghai. Methods The descriptive epidemiology analysis was conducted on sentinel surveillance data of infectious diarrhea from 7 sentinel hospitals in Ninghai. Results The sentinel surveillance data indicated that the incidence peak of infectious diarrhea was in July. Most patients were at the age of 0-10 years. The most affected populations were children outside child care settings and farmers. The incidence in rural area was obviously higher than in urban area. The disease was mainly caused by eating undercooked sea products and cross contamination; Vibrio parahemolyticus was the main pathogen in general population and rotavirus was the main pathogen among infants and young children. Conclusion The prevention and control of infectious diarrhea should be strengthened among rural population and children outside child care settings. It is necessary to improve the disease surveillance, public health facility, management of food and health education. The immunization rate of oral rotavirus vaccines for infants should be increased.