Abstract: OBJECTIVE To investigate the effect of an automated lumen pretreatment device on the cleaning quality of flexible endoscopes. METHODS A stratified block randomization design was adopted. A total of 90 endoscopes that were used in the Endoscopy Center of the First Hospital of Jilin University from May to Jun 2023 were enrolled and divided into two groups at a ratio of 1∶1. During the pre-cleaning stage, flexible endoscopes in the experimental group were treated with an automatic lumen pre-cleaning device for flexible endoscopes, while those in the control group underwent manual preprocessing. Differences in indicators such as ATP values after preprocessing, ATP values after cleaning, and patient turnover time were compared between the two groups. RESULTS The experimental group demonstrated superior ATP values after pre-cleaning and ATP decontamination rates in gastroscope, colonoscope subgroups and overall levels as compared to the control group (all P<0.001). The overall ATP decontamination rate was 96.86%. The overall pre-cleaning qualified rate of the experimental group was 60.00%, higher than the 24.44% of the control group (P=0.001). The experimental group showed significantly lower post-cleaning ATP values (all P<0.001) and a higher overall cleaning qualified rate (95.56% vs. 80.00%) than the control group did (P=0.050). The experimental group had a shorter mean patient turnaround time (179.40±7.02 s) than the control group (223.06±12.07 s) did (P<0.001), representing an average reduction of 43.66 s. CONCLUSIONS The automated lumen pretreatment device for flexible endoscopes significantly improves the pretreatment and cleaning efficacy and reduces patient turnaround time. It achieves dual optimization of healthcare quality and clinical efficiency, demonstrating substantial value for clinical promotion.