The invention discloses application of ellagic acid and tripterine for synergically preparing an anti-lung cancer drug. The ellagic acid exerts a better function and is used as a natural polyphenol material; in an animal experiment, the ellagic acid almost has no side effect and the serum index and the weight are both normal; under the synergic effect of ellagic acid and tripterine, the dosage of the tripterine can be reduced and no obvious side effect exists.