The invention relates to an action of ferulic acid on enhancing the drug effect of some medicaments and a purpose thereof, wherein the medicaments mainly comprise alkaloid medicaments including matrine, kushenin, sophocarpine, hyoscyamine, narceine, hanfangchin A, jamaicin, morphine, codeine, evodiamine, strychnine, catharanthine, vincristine, taxol, verticine, peimine, peiminine, ephedrine, pseudoephedrine, wilfordine, triptolide, tripdiolide and the like, and flavonoid medicaments including puerarin, ginsenoside, ginsengenin, mangiferin, scutelloside, alkannin, meletin, rutin, hesperidin, daidzin, soybean isoflavone, daidzein, carthamin, catechin and the like. The ferulic acid and the medicaments can form a compound or a medicament compound, or the ferulic acid and the medicaments can generate a chemical reaction (including salification, esterification, amidation, ketonization, etherification and the like), and/or the ferulic acid and the medicaments can generate a synergistic effect and an additive effect.