Objective To evaluate the curative effect and safety of Niaoshit on g pill in the treatment of urinary calculus.Method Multi- center randomized co ntrolled clinical trial was adopted. Three hundred and twenty cases were accepte d to the study, in which 200 cases were treated by Niaoshitong pill and 120 case s by Shilintong tablet as control. The effect of both groups was observed. Resul t 107 cases (53.5 % ) were cured, 53 cases(26.5 % ) effective, the total effe ctive rate being 80.0 % in the treatment group, and 27 cases(24.5 % ), 42 cas es (38.2 % ), and 62.7 % respectively in the control group. In a open group of 120 cases ,54 cases (45.0 % ) were cured, 44 cases (36.6 % ) were effective , the total effective rate being 81,6 % .Conclusion Niaoshitong pill can mark edly improve the clinical symptoms and exerts a strong lithagogue effect. It can promote the elimination of calculi after external blast lithotrity or ureterosc opic lithotrity, prevent the formation of 'stone street', and reduce the strictu re formed by the damage of ureter.