AIM To screen the active components of the Yao minority folk medicine Melastoma dodecandrum Lour.in reducing blood glucose.METHODS Extracted with 95% ethanol, the drugs Melastoma dodecandrum Lour.were subsequently extracted by skellysolve G, acetic ether, n-butyl alcohol and distilled water respectively.The diabetes mellitus models were induced by alloxan in mice, adrenaline and high concentration glucose were administrated respectively to induce experimental hyperglycemic mice.The mice were treated with corresponding drugs for 10 d and then the blood glucose levels were assayed.RESULTS The blood glucose levels were reduced significantly after 10 d in the mice that were treated with acetic ether extract and n-butyl alcohol extract respectively,compared with the model group.CONCLUSION The acetic ether extract and n-butyl alcohol extract of Melastoma dodecandrum Lout.could lower the blood glucose in hyperglycemic mice, and the acetic ether extract was more effective.