Despite differences in prostate cancer risk across ancestry groups, relative performance of prostate cancer genetic risks scores (GRS) for positive biopsy prediction in different ancestry groups is unknown. This cross-sectional retrospective analysis examines the association between a polygenic hazard score (PHS290) and risk of prostate cancer diagnosis upon first biopsy in male Veterans using two-sided tests. Our analysis included 36,717 Veterans (10,297 of African ancestry). Unadjusted rates of positive first prostate biopsy increased with higher genetic risk (low risk: 34%, high risk: 58%; p < .001). Among men of African ancestry, higher genetic risk was associated with increased prostate cancer detection on first biopsy (OR 2.18, 95% CI 1.93-2.47), but the effect was stronger among men of European descent (OR 3.89, 95% CI 3.62-4.18). These findings suggest that incorporating genetic risk into prediction models could better personalize biopsy decisions, although further study is needed to achieve equitable genetic risk stratification among ancestry groups.