OBJECTIVE To prepare apigenin silk fibroin（API@SF）nanoparticles and to evaluate their safety and anti-tumor activity. METHODS API@SF nanoparticles were prepared by nanoprecipitation method ，and their morphology ，particle size ，Zeta potential，drug loading amount and in vitro release were characterized. The safety of nanoparticles was evaluated by hemolysis test and HE staining. MTT assay was adopted to evaluate inhibitory effects of API@SF nanoparticles on breast cancer 4T1 cells in mice. RESULTS The prepared API@SF nanoparticles were spherical with uniform distribution. The average particle size was 406.61 nm， the polydispersity index was 0.154，the Zeta potential was －18.4 mV，and the average drug-loading amount was 5.20％. The in vitro release results showed that the release rate of the nanoparticles was relatively fast in the release medium of pH 5.0 and relatively slow in the release medium of pH 7.4. Results of hemolysis test and HE staining showed that the nanoparticles had good biocompatibility. Results of MTT assay showed that the inhibitory effect of API@SF nanoparticles on 4T1 cells was significantly higher than that of API raw materials （P＜0.05），and its mechanism may be related to increasing the level of reactive oxygen species in cells. CONCLUSIONS API@SF nanoparticles are prepared successfully ，which possess good safety and anti-tumor activity.