Disclosed are applications of Bouchardatine and Bouchardatine derivative in preparation of an anti-obesity and fatty liver-relieving drug. The structural fomulas of the Bouchardatine and the Bouchardatine derivative are shown in a pattern (I), to be specific, R is -(CH<2>)<n>R<1>, R<1>is substituted phenyl, heterocyclic radical or substituted amidogen, and n is equal to 0, 1, 2 or 3. By the use of the Bouchardatine and the Bouchardatine derivative, differentiation of pre-adipocyte 3T3-L1 is restrained so as to reduce lipid accumulation in adipocyte 3T3-L1; lipid accumulation, caused by sodium oleate, in hepatoma carcinoma cells is reduced, zooblast triglyceride level is lowered, and anti-obesity and fatty liver-relieving effect is achieved.