This article demonstrates that aloperine shows preferential antitumor effects in intrahepatic cholangiocarcinoma cells harboring the mutant IDH1 by decreasing D-2-hydroxyglutarate, suggesting that aloperine could be used as a lead compound or adjuvant chemotherapy drug to treat ICC harboring the mutant IDH. The gene discussed is IDH2; the disease is intrahepatic cholangiocarcinoma.