Abstract: The purpose of this study was to investigate the apoptosis of human gastric cancer MGC-803 cells induced by toosendanin and its mechanism, so as to provide reference for toosendanin in the treatment of gastric cancer. Fluorouracil and 0 nmol/L toosendanin（TSN） were used as positive control and negative control, respectively.Human gastric cancer MGC-803 cells were treated with TSN at a final concentration of 30 nmol/L, 50 nmol/L,and 70 nmol/L for 48 h, and the morphological structure of the cells was observed by laser confocal microscopy.Flow cytometry was used to detect the apoptosis rate, enzyme-labeled method was used to detect the activity of Caspase-3 and Caspase-8, RT-qPCR and Western blot were used to detect the gene expression level of Fas, Caspase-3 and Caspase-8. Compared with the 0 nmol/L TSN group, 30 nmol/L, 50 nmol/L, and 70 nmol/L TSN acted on human gastric cancer MGC-803 cells for 48 h, showing reduced cell size, nuclear lysis, and partial chromatin Morphological changes such as agglutination. The percentage of early apoptotic cells and late apoptotic cells increased significantly; the activity of Caspase-3 and Caspase-8 increased significantly; the mRNA and protein expression levels of Fas, Caspase-3 and Caspase-8 genes increased significantly. In summary, toosendanin can induce apoptosis of human gastric cancer MGC-803 cells through the death receptor pathway.