BACKGROUND AND AIMS: Computer-aided detection (CADe) systems have improved the adenoma detection rate (ADR). However, concerns about its long-term effect on endoscopists' performance without CADe and potential deskilling remain unknown. This study evaluated the impact of CADe on the learning curve of endoscopists for ADR. METHODS: This propensity score matching, prospective, single-center, observational study was conducted from January 2021 to December 2023. CADe systems were installed in half of the endoscopy units, and patients were equally distributed between the rooms. Patients aged >/= 20 years scheduled for colonoscopy were included, excluding those with polyposis, inflammatory bowel disease, known polyps, incomplete colonoscopy, emergency cases, previous colorectal surgery, and examination by novices. Endoscopists were classified as high detectors (ADR >/=25%) or low detectors (ADR <25%) based on the ADR recorded before CADe implementation. To assess skill acquisition and transfer, the primary outcome was to the change in ADR over time, as measured by cumulative summation analysis, in both CADe and non-CADe procedures. RESULTS: Of 18,962 patients who underwent colonoscopy, 13,245 patients were excluded, and of 5717 patients initially enrolled, 4712 patients (CADe group n=2356; non-CADe group n=2356) were analyzed after propensity score matching. Cumulative summation analysis showed that high and low detectors achieved enhanced detection performance among CADe procedures. Among non-CADe procedures, high detectors had accelerated learning curves indicating they maintained a higher ADR, whereas low detectors showed no significant change in their learning trajectory. CONCLUSIONS: After CADe implementation, detection rate in procedures performed without CADe was maintained and did not decline.