In a community survey of 19,410 people for 12 months in southeastern China (Fujian Province), the overall annual incidence rate of diarrhoea was 729.9 episodes/1,000 population. The incidence varied with different age groups; children aged under five years had the highest rate, 2.25 episodes per child per year. A bacterial pathogen was isolated from 883 cases (44.03%), and 147 (14.76%) strains from 996 healthy controls. Enterotoxigenic Escherichia coli, enteropathogenic E. coli, and Shigella species were the most frequently isolated bacterial pathogens. Isolation was highest during the hot summer months. The investigation showed that the diarrhoea incidence was related to the status of economy, education, healthy, hygiene, food, and water.