The repeatability of the 20-min pad test has not been reported. The aim of this study was to evaluate the test-retest reliability of the 20-min pad test in women with urodynamic stress incontinence. Among 89 enrolled women, 67 (75%) women were diagnosed with urodynamic stress incontinence and were examined in this study. The mean strong-desire volume of all the women was 306.7 ± 115.7 mL. The pad weights of the test versus retest were 28.3 ± 41.2 g versus 28.4 ± 38.6 g, p = 0.29, respectively. The test and retest pad weight results had a Spearman's rho of 0.788 (p < 0.0001). The intraclass correlation coefficient was 0.793 (95% confidence interval, 0.704-0.882; p < 0.0001). The Bland-Altman plots all revealed good agreement between the test and the retest in the pad weights. In conclusion, the 20-min pad test infused with a strong-desired volume has good test-retest reliability to assess the severity of urine leakage for women with urodynamic stress incontinence.