Abstract: Natural polysaccharides were attracted more attention on antitumor drug screening for its antitumor effect and low side effect.The antitumor mechanism of natural polysaccharides were refer to enhance the immune activity,change cell membrane fluidity,induce tumor cell cycle arrest or apoptosis,inhibit nucleic acid and protein synthesis,regulate the expression of tumor genes, etc.This article described the research progress of antitumor mechanism of natural polysaccharides through the regulation of p53 gene at home and abroad in recent years,which provided some references for future development and utilization of natural polysaccharides.

Key words: natural polysaccharides, p53 gene, cancer