Sann-Joong-Kuey-Jian-Tang (SJKJT), a traditional Chinese medicine, has been prescribed as complementary medication for colon cancer in Taiwan. However, its molecular mechanisms are not yet understood. In the present study, we investigated the effects of SJKJT on human colon cancer colo 205 cells in vitro. The cytotoxicity of SJKJT in colo 205 cells was evaluated using the MTT assay, and the protein expression of microtubule-associated protein II light chain 3 (MAP-LC3-II) was measured using Western blot analysis. The results showed that SJKJT inhibited the survival rates of colo 205 cells in a time- and dose-dependent manner, with an IC50 concentration at 24 h of 590.34 µg/ml. In addition, SJKJT up-regulated the protein expression of MAP-LC3-II in colo 205 cells. These findings indicate that one of the molecular mechanisms by which SJKJT inhibits the proliferation of colo 205 cells in?vitro may be through the induction of the autophagic pathway. SJKJT may therefore have therapeutic potential for the treatment of human colon cancer.