The invention relates to a Chinese medicine compound preparation for treating diabetes mellitus. The preparation comprises the following compositions: 0.1 to 99 percent of mulberry (a mulberry leaf or/and mulberry branch or/and white mulberry root-bark or/and mulberry syncarp), 0.1 to 99 percent of cassia cinnamon, 0.01 to 20 percent of hydrangea aspera don, 0 to 50 percent of stevia, 0 to 50 percent of rhizoma anemarrhenae, 0 to 50 percent of rhizoma polygonati, 0 to 15 percent of folia eriobotryae, 0 to 50 percent of radix platycodi, 0 to 50 percent of rehmanniae, 0 to 50 percent of radices saussureae, 0 to 50 percent of faenum graecum, 0 to 50 percent of radices puerarire, 0 to 50 percent of rhizoma atractylodis, 0 to 50 percent of radices pseudoginseng, 0 to 50 percent of glossy ganoderma, 0 to 50 percent of rhizoma atractylodis alba, 0 to 50 percent of acanthopanax, 0 to 50 percent of herba epimedii, 0 to 50 percent of Chinese yam, 0 to 50 percent of cortex acanthopanacis radicis, 0 to 50 percent of fructus corni, 0 to 50 percent of fructus mume and the like. The raw materials are decocted with water for 10 to 120 minutes to be filtered to obtain an extracting solution; and after the extracting solution is dried by concentration, the concentrated substance can be capsulated or tabletted; or the extracting solution can be concentrated to half to one twentieth of the weight of Chinese medicine raw materials, and the concentrated solution is sterilized and bottled. The product has obvious hyperglycemic effect according to 1 to 50 grams or 5 to 500 milliliters of concentrated solution per person everyday.