Objective To investigate the efficacy and safety of Ningdong granule on Obsessive-compulsive disorder (OCD) associated with Tourette's syndrome (TS).Methods Thirty-six patients with OCD associated with TS were randomly divided into 2 groups.18 patients in the treatment group were treated with ND granule,and 18 patients in the control group were treated with fluoxetine,the initial dose of fluoxetine was 10 mg/d,and maximum dose was 60 mg/d.All of the participants with history of medication had to be medication-free for≥ 1 weeks prior to the study.The severity of tics and OCD were evaluated at baseline and at end point (8 w),with Yale Global Tic Severity Scale (YGTSS)and Yale-Brown Obsessive Compulsive Scale (Y-BOCS),the contents of 5-HT in serum were measured by ELISA.Side-effects were evaluated according to an adverse event chart produced by this study team.Results The effective rate of treating tics in treatment group was 88.89％ (16/18),and in control group was 77.78％ (14/18).The effective rate of treating OCD in treatment group was 83.33％ (15/18),and in control group was 88.89％ (16/18).The differences in the aspects between treatment group and control group were not significant (P＞0.05).Compared with YGTSS scores [the treatment group was (27.28 ± 8.10),the control group was (29.17 ± 7.53)] and Y-BOCS scores [the treatment group was (22.72 ± 6.75),the control group was (23.17 ± 6.12)] at baseline,the scores YGTSS scores [the treatment group was (12.72±5.20),the control group was (15.50±5.39)] and Y-BOCS scores [the treatment group was (1250± 4.38),the control group was (12.22±4.31)] of both two groups at end point reduced significantly (P＜0.01),but the difference between the two groups was not significant (P＞0.05).The contents of serum 5-HT in the two groups were significantly raised after treatment [the treatment group was (86.05±24.26 vs 66.00±19.63) ng/ml,P=0.01),the control group was (91.16±26.07 vs 67.52±21.18) ng/ml,P＜0.01].Only one subject reported adverse reactions in the treatment group,while 6 subjects experienced adverse reactions in the control group,but no difference was shown in comparison of the aspect between the treatment group and the control group (P＞0.05).Conclusion ND granule with tiapride could improve the syndrome of tics and OCD associated with TS.ND granule with tiapride and fluoxetine with tiapride showed similar efficacy and safety for OCD with TS.