A QuEChERS method was developed to simultaneously quantify isoprothiolane and tebuconazole in paddy field samples by using UPLC-MS/MS. The method has been successfully applied in determining isoprothiolane and tebuconazole in brown rice, polished rice, rice husk and straw. The dissipation behaviour of isoprothiolane and tebuconazole in rice followed first-order kinetics, with a linear correlation coefficient of 0.8283 to 0.9877. The degradation half-life of isoprothiolane in rice grain was 6.5–25.7 days, whereas that of tebuconazole was...