Abstract: Field experiments were conducted to study the residues and dissipation of matrine in Brassica rapa L.chinensis Group. and soil in spring and winter. The C18 solid phase extraction combined with high performance liquid chromatography (HPLC) analysis method was established to determine the content of matrine in pakchoi and soil. The recoveries of matrine in pakchoi and soil were 71%-87%, with relative standard deviations (RSDs) of 5.7%-14%. The limit of quantity (LOQ) of matrine in pakchoi and soil were both 0.02 mg/kg. The degradation results indicated the dissipation of matrine in pakchoi and soil accorded with the first-order kinetic equations, the half-lives were 1.0 d (spring, pakchoi), 1.5 d (winter, pakchoi), 1.4 d (spring, soil) and 1.6 d (winter, soil), respectively. 7 days after the last spraying, the final residues of high (6.71 g a.i./hm2) and low (4.47 g a.i./hm2) concentrations in pakchoi were 0.061-0.074mg/kg. However, the contents in soil were from nondetected to 0.075 mg/kg under the same conditions. The results demonstrated that the residues of matrine in pakchoi and soil were easy to be degraded. To ensure the safety, 0.1 mg/kg was recommended as maximum residue limit (MRL) of matrine in pakchoi, and 3 days was suggested as the safe interval period.