This study is designed in a randomized, double-blind, placebo controlled, multicentric trial. A total of 60 patients will be enrolled. All patients have suffered from dysfunctional voiding that is refractory to conventional treatment. The enrolled patients should have severe dysuria or urinary retention, large residual urine and have been treated with medication or other therapeutic modality for over 3 months. The patients will be randomly assigned to allocate in the treatment and control groups in a 2:1 ratio. About 40 and 20 patients will be enrolled in the treatment and control group, respectively.