The invention discloses a pharmaceutical composition with the effects on eliminating heat, reducing fire and detoxifying, a preparation method and a quality control method thereof. The crude drugs of the pharmaceutical composition of the invention comprise coptis, Chinese rhubarb and scutellaria; the preparation method comprises the steps that: the three raw materials are respectively added with water and decocted for 2 to 3 times; for each time, 6 to 9 times of water is added and decoction is done for 1 to 2 hours; the decoction solutions of each raw material are mixed and filtered; the filtrate is condensed till obtaining an approximate relative density of 1.25 (measured under 65 to 75 DEG C), and then sprayed and dried to obtain dry extract; the three dry extracts are added with properamount of cane sugar and dextrin, well mixed, pelletized and then dried so as to obtain 1000g of granules, and finished product is obtained. The invention adopts high performance liquid chromatography to determine the content of baicalin. The pharmaceutical composition of the invention has good effect on eliminating heat, reducing fire and detoxifying.