TW9183 is a new compound synthesized in our laboratory that has been entered preclinical trials in China for developing it into a new anticarcinogenic medicine. In this study, we aimed to investigate the antitumor effects of the compound on A549 and SMMC-7721 cells. We found that the TW9183 showed better proliferation-inhibitory effects on SMMC-7721 tumor cells (IC50 = 1.586 μmol/l) than A549 cells with time and dose dependent. TW9183 also inhibited colony formation (7.06% at 2 μmol/l and 0.72% at 8 μmol/l respectively) and cell migration in A549 and SMMC-7721 cell lines. TW9183 induced G2/M arrest in A549 cells and SMMC-7721 cells. The study indicated that TW9183 may have potent antitumor effects on human lung and hepatitis cancers.