Provided in the present invention is a pharmaceutical composition containing an imidazoline derivative. In particular, the pharmaceutical composition provided in the present invention contains (S)-4-(3-(4-(2,3-dihydroxypropoxy) phenyl)-4,4-dimethyl-5-carbonyl-2-thioxoimidazolidin-1-yl)-2-(trifluoromethyl) benzonitrile and cellulose ether; the composition has good stability, dissolution rate and bioavailability.