The invention provides a fluorine-containing compound, a preparation method thereof, and an application of the compound in the preparation of antitumor drugs. The compound has a structure representedby formula (I); and in the formula (I) -CF3 and R are substituent groups on a benzene ring, and R is selected from hydrogen, an alkyl group, a haloalkyl group, an alkoxy group and halogen. The invention also provides pharmaceutically acceptable salts of the compound of formula (I). The compound has a good inhibitory activity on proliferation of bile duct cancer cells and human pancreatic cancer cells, and is significantly superior to clinically applied fluorouracil.