Purpose: To analyze the effect of the size of posterior urethrovesical angle (PUVA) changes on the efficacy of surgical incontinence treatments. Materials and Methods: This study included 126 patients with stress urinary incontinence. The patients were randomized into transobturator tape (TOT) and retropubic sling (RPS) groups. Ultrasonographic PUVA measurements were taken at rest and during the Valsalva maneuver before and after the operation. The efficiency of the operation and the size of the changes in PUVA measurements in the TOT and RPS groups were analyzed. Results: There were 66 patients in the TOT group and 60 patients in the RPS group. In both groups, there were statistically significant differences between preoperative and postoperative PUVA values (p < 0.05). When all patients were analyzed, the objective cure rates in patients with changes of < 20° or > 20° were 65.9% and 87.8%, respectively (p = 0.009: OR: 3.52 (1.33–9.28). Conclusion: Intraoperative efforts to maintain a PUVA difference of more than > 20° may help to increase the surgical success of TOT and RPS operations.