The invention relates to Chinese medicinal decoction used for treating lithiasis and a preparation method thereof, and relates to Chinese medicinal decoction for treating biliary calculus and renal calculus diseases. Main components of the decoction comprise ophiorrhiza pumila, dandelion, rhizoma sparganii, zedoary, white paeony root, herba pyrrosiae, bupleurum, Szechuan lovage rhizome, peach kernel, radix curcumae, gizzard lining, curcuma, knotgrass, gardenia, dried old orange peel, immature tangerine peel, liquorice and the like. The Chinese medicinal decoction can effectively heal intrahepatic bile duct calculus after the gall bladder is extirpated and calcification and sand-like calculus in the kidney, and simultaneously can effectively promote choleresis, improve the self-healing function of the gall bladder, and recover the functions of the gall bladder and the kidney.