Successive cartridge clean-up method for the simultaneous determination of matrine and oxyma- trine in biopesticides containing Sophora flavescens extract was developed and validated by UPLC. The clean-up method was established with ENVI-Carb (0.5 g) and C₁₈ SPE (0.5 g) cartridges for the bioactive alkaloid in biopesticides from S. flavescens, and the eluate was analyzed to quantify the matrine and oxymatrine by UPLC. The developed method was validated, and the recovery and LOQ of both materials were 105.0% and 103.6%, and 0.050 and 0.684 mg·kg^-1, respectively. Of the twenty one samples, the total content of matrines were analyzed by using the developed method and the result showed the developed successive clean-up method could contribute to the manufacture and control of biopesticides including matrines, and can be ap- plied to the method development for the analysis of alkaloid materials in biopesticides.