Abstract： This study is to investigate the effect of valve ablation on bladder function in patients with posterior urethral valves. The clinical data of patients with posterior urethral valves who received urodynamic examination before and after valve ablation were retrospectively analyzed.The bladder compliance improved during urine storage after operation, and the maximum detrusor pressure decreased during micturition. The postoperative urinary system ultrasound showed that the residual urine volume of the group with significantly improved upper urinary tract hydrocephalus was significantly less than that of the group with no improvement. The bladder compliance was significantly higher than that of the group with no improvement, and the maximum urine flow rate was significantly higher than that of the group with no improvement (all P<0.05). Valve ablation has limited effect on improving bladder function in patients with PUV. Valve incision can help improve the maximum bladder volume, residual urine volume and maximum urinary flow rate. It has a certain effect on bladder compliance and maximum detrusor pressure.