The present invention provides a novel molecule marker for resistance to an anticancer agent for biliary tract cancer, and diagnostic and therapeutic uses thereof. The marker, according to the present invention, shows significantly increased expression in an anticancer agent-resistant biliary tract cancer cell line compared to a non-anticancer agent-resistant biliary tract cancer cell line. By inhibiting the expression of protein in the marker according to the present invention, sensitivity of anticancer agent-resistant biliary tract cancer to the anticancer agent can be increased.
