Objective To explore the application effect of FOCUS-PDCA model (find, organize, clarify, understand, select, plan, do, check, act) in improving the pre-cleaning process of flexible endoscopes. Methods Totally 19 920 cases of digestive endoscopes used for diagnosis and treatment before the implementation of FOCUS-PDCA model from March to May 2018 were taken as the control group and 12 700 cases of digestive endoscopes used after the implementation of FOCUS-PDCA model from June to July 2018 were taken as the observation group. The pre-cleaning process was carried out according to WS 507-2016 Technical Specification for Endoscopic Cleaning and Disinfection in the control group. The FOCUS-PDCA model was carried out in the observation group to analyze the factors affecting the quality of flexible endoscopy pre-cleaning, establish a continuous quality improvement group to improve and standardize the process, analyze and compare the two groups in terms of the flexible endoscope water and gas pipeline blockage rate and endoscopy nurses' related knowledge; sampling and compare the pre-cleaning performance and manual cleaning quality between the two groups. Results The qualified rates of flexible endoscopes pre-cleaning and manual cleaning were 95.56% and 94.50% respectively, which were significantly higher than the control group (81.50% and 86.50%) with statistical difference (χ2=135.285, 7.444; P<0.05) . The blockage rate of water and gas pipelines in the control group was 0.26%, higher than the observation group (0.03%) with statistically significant difference (χ2=23.228, P<0.001) . The score of endoscopy nurses' knowledge increased from (75.0±6.071) to (87.6±4.823) , and the difference was statistically significant (t=12.734, P<0.001) . Conclusions The application of FOCUS-PDCA model to manage, improve and standardize the pre-cleaning operation process effectively improves the qualified rate of pre-cleaning execution and manual cleaning, reduces the blockage rate of water and gas pipelines in flexible endoscopes, and ensures the quality of endoscopy reprocessing. Key words: FOCUS-PDCA model; Flexible endoscopes; Pre-cleaning; Cleaning quality