Colorectal cancer is one of the most common causes of cancer-related death in humans. Coptisine (COP) is a natural alkaloid from Coptidis Rhizoma with unclear antitumor mechanism. Human colon cancer cells (HCT-116) and xenograft mice were used to systematically explore the anti-tumor activity of COP in this study. The results indicated that COP exhibited remarkably cytotoxic activities against the HCT-116 cells by inducing G1-phase cell cycle arrest and increasing apoptosis, and preferentially inhibited the survival pathway and induced the activation of caspase proteases family of HCT-116 cells. Experimental results on male BALB/c nude mice confirmed that orally administration of COP at high-dose (150 mg/kg) could suppress tumor growth, and may reduce cancer metastasis risk by inhibiting the RAS-ERK pathway in vivo. Taken together, the results suggested that COP may be potential as a novel anti-tumor candidate in the HCT-116 cells-related colon cancer, further studies are still needed to suggest COP for the further use.