Investigations on the relationship between angiotensin-converting enzyme (ACE) insertion/deletion (I/D) gene polymorphism and prostate cancer risk are conflicting. This meta-analysis was conducted to assess the relationship between ACE I/D gene polymorphism and prostate cancer risk. Reports were identified from PubMed, Cochrane Library, and China Biological Medicine (CBM)-disc (CBM database) on December 30, 2014, and eligible studies were recruited. ACE I/D gene polymorphism was not associated with prostate cancer risk for overall populations in this meta-analysis (D allele: Odds ratio [OR] =1.56, 95% confidence interval [95% CI]: 1.00-2.46, P = 0.05; DD genotype: OR = 1.74, 95% CI: 0.95-3.20, P = 0.07; II genotype: OR = 0.67, 95% CI: 0.39-1.15, P = 0.15). Furthermore, the association of ACE I/D gene polymorphism with colorectal cancer risk was not found for the Caucasians. Interestingly, ACE I/D gene polymorphism was associated with prostate cancer risk for the Asian population and Latino population. There was an association between ACE I/D gene polymorphism and prostate cancer risk for the Asians and Latino population in this meta-analysis. However, more investigations should be performed to confirm this relationship.