The invention discloses a new compound and the usage, in particular to a 4-hydroxy-2, 3- dimethoxy -6-methyl-5 (3, 7, 11- trimethyl-2, 6, 10-dodecatrien) -2- cyclohexenone (4-hydroxy- 2, 3-dimethoxy -6- methy-5 (3, 7, 11-trimethyl -dodeca-2, 6, 10- trienyl) -cyclohex-2-enone) separated from antrodia camphorate extract and the application in inhibiting the growth of tumor cell. The new compound isfirstly seen in antrodia camphorate. The 4-hydroxy-2, 3- dimethoxy -6-methyl-5 (3, 7, 11- trimethyl-2, 6, 10-dodecatrien) -2- cyclohexenone (4-hydroxy- 2, 3-dimethoxy -6- methy-5 (3, 7, 11-trimethyl -dodeca-2, 6, 10- trienyl) -cyclohex-2-enone) separated from antrodia camphorate extract and the application in inhibiting the growth of tumor cell has the advantages of inhibiting the growth of breast cancer, liver cancer and prostate cancer tumor cell, being a component of drug combination inhibiting the growth of the tumor cell at the same time or further being applied in preventing cardiovascular disease or being added into healthy food by right of antioxidant activity.