The present invention relates to a field of pharmaceutical chemistry, more specifically, the present invention relates to a garcinia derivative Formula (I), its preparing method, and medicinal use. Wherein the definitions of R1 and R2 are disclosed in the specification of the present invention, and the derivative of the present invention is a structurally simplified analogue of the gambogic acid compound wherein the gambogic acid compound possesses anti-cancer characteristics, and could be used for preparation of anti-tumor drugs.