The invention discloses powders, a decoction, and pills used for treating diabetes mellitus. Through syndrome differentiation, licorice root, gypsum, skunk bugbane rhizome, lobed kudzuvine root, and snakegourd root are adopted in a powder; common jujube, licorice root, ginseng, cochinchinese asparagus root tuber, creeping liriope, ternate pinellia are adopted in a powder; rhubarb, ligusticum, incised notopterygium rhizome and root, Chinese ephedra herb, cochinchinese asparagus root tuber, and peach seed are adopted in the pills; and licorice root, largehead atractylodes rhizome, dried ginger, ginseng, snakegourd root, and prepared rehmannia rhizome are adopted in the decoction. Therefore, diabetes mellitus can be cured or relieved, and urine glucose can be reduced.