Intestinal infectious disease is one of the most common diseases in China and is prevalent worldwide. The Chinese government launched a toilet improvement campaign to improve sanitation and reduce the incidence of diseases. This study determined the association between sanitary toilet use and intestinal infectious disease incidence in Jiangsu Province, China during 2011-2019. This study adopted an ecological retrospective research design. All secondary data were obtained through government websites and government information disclosure channels. Multiple linear regression was employed to analyze the association between the incidence of intestinal infectious diseases and sanitary toilet coverage rate and other potential predictors. Data suggested that the aggregate annual incidence of Type A and B intestinal infectious diseases showed a downward trend, the aggregate annual incidence of other infectious diarrhea continued to increase, and hand-foot-mouth disease occurred every other year with the highest annual incidence rate. The incidence was higher in coastal cities. Multiple regression results indicated that the usage of three types of sanitary toilets, compliance rate of water quality, and average ambient temperature have an impact on intestinal infectious diseases. The aggregate annual incidence of Type A and B intestinal infectious disease was negatively correlated with the cumulative use of sanitary toilets (β = - 0.036) and surface water quality (β = - 0.135; p < 0.05). Increase in sanitary toilet use and water quality control can reduce the number of new cases, which will be beneficial for the population in the province. Moreover, the toilet improvement interventions should continue to maintain high-quality construction.