The invention relates to application of echinacoside in anti-tumor medicaments. The application provided by the invention is as follows: firstly adding MTH1, inorganic pyrophosphatase and dGTP into a reaction solution (100mM pH 8.0 Tris-acetic acid, 40mM NaCl, 10mM magnesium acetate, 0.005% Tween 20 and 1mM DTT), incubating an enzyme and a substrate at room temperature for 1h, then adding 25 mu l of malachite green solution to terminate reaction and performing absorbance detection at 630nm by using an iMark microplate reader, wherein results show that echinacoside has a significant effect of inhibiting enzyme activity of MTH1; and secondly detecting the effects of echinacoside against tumor cells at the cellular level by an MTT experiment, wherein the results show that echinacoside can obviously inhibit the growth of SW480 colon cancer cells and U2OS human osteosarcoma cells. According to the application provided by the invention, echinacoside is used for inhibiting specific enzyme MTH1 for maintaining survival in the tumor cells, and oxidized nucleotide is mixed into DNA, thereby resulting in fatal DNA double-strand break in the cancer cells, producing an anti-tumor effect, finding a new medical use of echinacoside and laying a foundation for future development of the new anti-tumor medicaments.