ObjectiveTo investigate the incidence of perianal surgical site infection（SSI）in patients with anorectal diseases in hospitals in Wuhan on the basis of “The diagnostic criteria for perianal SSI in anorectal diseases”. MethodsEpidemiological prospective survey was adopted, five  hospitals in Wuhan were selected to collect information, the relevant factors for perianal SSI, including age, sex, occupation, obesity, history of diseases, duration of operation, anaesthesia, change in the number and species of bacteria at incisional site（including perianal）, and hospitalization time and costs were analysed, SSI was evaluated according to the newly established “diagnostic criteria”. ResultsThe overall rate of perianal SSI in anorectal diseases was 32.98 %（124/376）. SSI in hemorrhoid (including internal and external hemorrhoid, mixed hemorrhoid, rectal polyp,and anal fissure) was 29.06％（77/265）, SSI in perianal abscess and  anal fistula was 38.46％（15/39） and 44.44％（32/72）respectively.Statistical analysis showed that perianal SSI was relevant to patients’ hospital stay （P<0.05）, the percentage of changes in the number and species of bacteria at surgical sites was 24.50% and 30.46% respectively.ConclusionThis survey acquired the epidemiological data about perianal SSI in patients with anorectal diseases in Wuhan, which provide the scientific basis to prevent and control perianal SSI in anorectal diseases.