OBJECTIVES: To assess the effects of blue-light (BL)-enhanced transurethral resection of bladder tumour (TURBT) compared to white-light (WL)-based TURBT in the treatment of non-muscle-invasive bladder cancer (NMIBC). METHODS: Based on a published protocol, we performed a systematic search of multiple databases from their inception to March 2021. We included randomized controlled trials (RCTs) comparing blue-light (BL) TURBT to white-light (WL) TURBT. Our meta-analysis was based on a random-effects model. We assessed the quality of evidence on a per-outcome basis according to the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach. RESULTS: We included 16 RCTs involving a total of 4325 participants in this review. BL TURBT may reduce the risk of disease recurrence over time (hazard ratio [HR] 0.66, 95% confidence interval [CI] 0.54-0.81; low-certainty evidence) depending on baseline risk. For participants with low-, intermediate- and high-risk NMIBC, this corresponded to 48 (66 fewer to 27 fewer), 109 (152 fewer to 59 fewer) and 147 (211 fewer to 76 fewer) fewer recurrences per 1000 participants when compared to WL TURBT, respectively. BL TURBT may also reduce the risk of disease progression over time (HR 0.65, 95% CI 0.50-0.84; low-certainty evidence) depending on baseline risk. For participants with low-, intermediate- and high-risk NMIBC, this corresponded to 1 (1 fewer to 0 fewer), 17 (25 fewer to 8 fewer), and 56 (81 fewer to 25 fewer) fewer progressions per 1000 participants when compared to WL TURBT, respectively. CONCLUSIONS: Our findings suggest a favourable impact of BL TURBT on the risk of disease recurrence and progression; however, whether this risk reduction is clinically relevant greatly depends on the baseline risk of patients. We did not find an increase in severe surgical complications with BL cystoscopy, and we did not find any trial evidence on other, non-surgical adverse events.