Objective The objective benefit of trans-vaginal mesh (TVM) on the storage function of the bladder in pelvic organ prolapse (POP) patients waits to be established. This study investigated if TVM improves the bladder storage by specifically focusing on its effects on the compliance. Design A retrospective cohort study Setting A medical center Population Female patients with voiding dysfunction who underwent TVM for prolapse stage ≥ II (POP Quantification system) and received urodynamic investigations before and after the operation. Methods: Data of pressure-flow cystometry and the derived pressure-volume analysis (PVA) were analyzed. Main outcome measures Bladder compliance, infused volume, and threshold pressure. Results Compared with the pre-operative control, TVM consistently and significantly increased the mean compliance of the filling stage (Cm; p<0.05 N=22); and further analyses demonstrated TVM increased the compliance of the late half (C2/2; p<0.01, N=22), while it exhibited insignificant effects on that of the early half (C1/2; p>0.05, N=22) of the filling stage. Moreover, without affecting the infused volume (Vinf; p>0.05, N=22), TVM decreased the threshold pressure (Pthd; p<0.01, N=22) and post-voided residual volume (Vres; p<0.05, N=13). Conclusions TVM improve storage function of POP patients via increasing bladder compliance, particularly at the late filling stage for it restored anatomical location and geometric conformation for bladder expansion. In addition, TVM also ameliorated voiding dysfunctions as it reduced urine retention, a symptom could lead to upper urinary tract damage and/or urinary incontinence.