A series of new allylated mono-carbonyl curcumin analogues (MACs) were designed and synthesized. In vitro cytotoxic activities of allylated MACs 6a-h together with previously reported analogues 4a-i and 7a-e, were tested against human cholangiocarcinoma cell lines including HUCCA, QBC-939 and RBE. Of all the compounds tested, 6c exhibited potent in vitro antiproliferative activity against the three tested cancer cell lines with IC50 values of 8.7, 9.3 and 8.9μM, respectively. Cell cycle analysis showed that 6c inhibited cell proliferation due to G2/M arrest. Furthermore, mechanistic studies revealed that 6c dose-dependently increased the level of Bax and inhibited the expression of Bcl-2, to induce cancer cell apoptosis. Taken together, this work provides a novel series of anti-cancer candidates for the treatment of cholangiocarcinoma.