Background: Cyclin B plays a crucial role in cancer cell cycle progression and is overexpressed in many human cancers, including breast cancer. However, the prognostic value of cyclin B expression in breast cancer is controversial. We performed a meta-analysis to assess the clinicopathological and prognostic significance of cyclin B expression in breast cancer. Methods: We searched PubMed, web of science, and Embase databases to retrieve the publications investigating the association between cyclin B expression and clinicopathological/prognostic significance in breast cancer patients. The pooled hazard ratio (HR) or odds ratio (OR) with its 95% confidence intervals (CIs) were used to estimate the effects. Results: Ten studies with 2366 breast cancer patients were included to evaluate the association between cyclin B expression and overall survival (OS), disease-free survival (DFS), disease-specific survival (DSS), and clinicopathological parameters. The results showed that cyclin B overexpression in breast cancer patients was significantly associated with both poor OS (univariate analysis: HR=2.38, 95% CI=1.72-3.30, P<.001), DFS (univariate analysis: HR=1.86, 95% CI=1.50-2.32, P<.001; multivariate analysis: HR=1.75, 95% CI=1.22-2.52, P=.003), and DSS (multivariate analysis: HR=5.42, 95% CI=2.15-13.66, P<.001). Additionally, cyclin B overexpression was significantly associated with lymphatic invasion (OR=2.58, 95% CI=1.03-6.46, P=.017). Conclusion: Cyclin B overexpression appears to be an independent potential prognostic marker to DSS and DFS for breast cancer. Further studies with large sample size are needed to dissect the relationship between cyclin B and clinicopathological features or prognosis of breast cancer.