To evaluate whether the risk of prostate cancer was different according to the pattern of fluctuation in prostate-specific antigen (PSA) levels in patients undergoing repeat transrectal ultrasound-guided prostate biopsy (TRUS-Bx). From March 2003 to December 2012, 492 patients underwent repeat TRUS-Bx. The patients were stratified into 3 groups based on the PSA fluctuation pattern: group 1 (continuous elevation of PSA, n=169), group 2 (PSA fluctuation with PSA velocity [PSAV]=1.0 ng/mL/yr, n=123), and group 3 (PSA fluctuation with PSAV<1.0 ng/mL/yr, n=200). Prostate cancer was detected in 112 of 492 patients (22.8%) in the repeat biopsy set. According to the PSA fluctuation pattern, prostate cancer detection rates at repeat TRUS-Bx were 29.6% (50/169) for patients with continuously increasing PSA, 30.1% (37/123) for PSA fluctuation with PSAV ≥1.0 ng/mL/yr, and 12.5% (25/200) for PSA fluctuation with PSAV <1.0 ng/mL/yr. Multivariate analysis showed that PSA fluctuation pattern and high grade prostatic intraepithelial neoplasia at initial TRUS-Bx were the predictive parameters for positive repeat biopsies. Among the 96 patients (85.7%) who underwent radical prostatectomy, no significant differences in pathologic outcomes were found according to the PSA fluctuation pattern. The current study shows that the risk of prostate cancer at repeat TRUS-Bx was higher in men with a fluctuating PSA level and PSAV=1.0 ng/mL/yr than in those with a fluctuating PSA level and PSAV<1.0 ng/mL/yr.