As a traditional Chinese herb, dandelion, containing complicated active ingredients which includes polysaccharide, flavonoid, terpene, pigment, phytosterol, coumarin, organic acid and etc, plays significant roles in various physiological activities in organisms. The active ingredients generally interfere in signal transduction of cancer cells, regulate cell cycle and apoptotic protein expression, inhibits proliferation and migration of cancer cells and etc, to effectively restrain tumor development and deterioration. This article summarizes the anti-tumor mechanism of five active ingredients in dandelion through paper reading which provides thoughts and references for anti-tumor research.