Background Obsessive-compulsive disorder(OCD)is considered a very debilitating disorder with severe loss of quality of life and income.Aims This study estimates the quality of life and economic consequences of OCD in China.Methods The research team interviewed 639 patients with OCD in 13 hospitals in 12 cities in China.The direct method was used to get the direct cost of OCD.Indirect costs associated with OCD were estimated using the human capital approach.Linear regression analysis was conducted for quality of life and generalised linear model analysis was conducted for total cost.Sensitivity analysis was used to analyse the uncertainty of total cost.Results The mean quality of life score for OCD was 52.78(20.46).The annual total cost of OCD per capita was 24 503.78(95％CI:22 621.53 to 26 386.03)renminbi(RMB)(US$3465.88(95％CI:US$3199.65 to US$3732.11)).The annual cost of OCD in China was estimated to be 37.74 billion(95％CI:34.95 billion to 40.53 billion)RMB(equal to US$5.34 billion(95％CI:US$4.94 billion to US$5.73 billion)).Sensitivity analysis showed that the total annual cost of OCD in China was between 23.15 billion RMB(US$3.27 billion)and 370.00 billion RMB(US$52.33 billion).Worse social function status,more psychiatric symptoms and higher Yale Brown Obsessive-Compulsive Scale(Y-BOCS)score were associated with worse quality of life.The numbers of clinic visits and hospitalisations,socioeconomic status,education,Y-BOCS scores and age were found to be significantly associated with total cost.Conclusions OCD is associated with low quality of life and high costs in China.The findings call for concerted efforts to improve services for patients with OCD.Improvements may include early detection and diagnosis,the provision of evidence-based treatments and relapse prevention strategies.