The invention relates to the technical field of traditional Chinese medicine, in particular to a medicine composition for treating benign prostatic hyperplasia and a preparation method thereof. The medicine composition is prepared from the following ingredients of cassia twig, cortex cinnamomi, poria cocos, cortex moutan, peach kernel, radix paeoniae alba, radix cyathulae, safflowers, processed armadillo scales, radix angelicae sinensis, leeches, radix bupleuri, aquilaria sinensis slices, semen vaccariae, liquorice roots, mole crickets, crickets, seeds of Chinese dodder, fructus lycii, semen plantaginis, frankincense, raw radix astragali, raw rhizoma dioscoreae and muskiness. The medicine composition has the advantages that the curative effect is obvious; the effects are clear; the multi-target effect is achieved; and no side effect exists.