ObjectiveTo study the current situation and influencing factors of biofilm formation of digestive endoscopy in Zhongshan Hospital, Fudan University.MethodsFrom September 1st to 13th, 2020, ATP fluorescence assay and membrane filtration method were carried out on 130 endoscopes from the Endoscopy Center of Zhongshan Hospital, Fudan University. The type, number, source, duration of use and disinfection times in the past week were collected. Positive culture samples were identified by matrix-assisted laser desorption / ionization time of flight mass spectrometry. Logistic regression analysis was used to explore the factors affecting the formation of biofilms.ResultsThe total qualified rate of ATP assay and bacterial culture was 94.62% and 92.31% respectively. The 10 positive culuture samples were mainly composed of Pseudomonas aeruginosa, Moraxella osloensis, Stenotrophomonas maltophilia, Pseudomonas putida and Micrococcus luteus. Multivariate logistic regression analysis showed that the frequency of disinfection in the past week was associated with positive biofilm culture (P=0.001). The odds ratio of disinfection frequency more than 30 times in past week compared with disinfection frequency less than 15 times was 0.040, and 95% confidence interval was (0.005, 0.295).ConclusionsThe biofilm of digestive endoscopy in the Endoscopy Center of Zhongshan Hospital, Fudan University is mainly formed by aquatic bacteria. The formation biofilm can decrease by increasing disinfection frequency, and attention should be paid to the monitoring of endoscopic biofilm in the future.