Objectives To investigate the effective methods of establishing the rat model of stress urinary incontinence (SUI). Methods 50 Sprague - Dawley rats were caged male and female together (co-cage ratio of 4:1), were randomly divided into two groups after giving birth, the first group (12) and the second group (28). To the first group, we only choose conventional breeding, without any special treatment. The second group we choose female rats after vaginal labour. Their vagina canal was overspread by air ballonet for 4 hours to simulate delivery trauma. Two weeks after the vagina was overspread with the same method again. After another one month ovariectomy was performed on them then conventional breeding for eight weeks, after underwent urodynamic testing maximum bladder capacity (MBC) and abdominal leak point pressure (ALPP) and the sneeze test, after urodynamic testing we randomly choose 12 femal rats stress urinary incontinence (SUI) models from the second group ss for the experimental group(stress urinary incontinence SUI model). Results The modified abdominal leak point pressure of control group and experimental group were (48.00 ± 1.74) cmH2O and (32.94±1.63) cmH2O,the difference was significant (p＜0.05); the maximum cystometries were (2.02±0.19) ml and (1.29±0.16) ml, the difference was significant (p＜0.05); sneeze test, the positive rates of sneeze test of model rat were 13/15(52%), All of the control rats were negative. Conclusions Stress urinary incontinence rats model can be successfully established by vagina balloon dilatation combined with ovariectomy.