Abstract: AIMTo assess the effects of the α-glucosidase inhibitor Sangzhi (Ramulus mori, SZ) on the relief of diabetic symptoms of hyperglycemia and the prevention of its late complications in alloxan diabetic rats with high-calorie chow. METHODS The aqueous extract of Sangzhi was given orally to alloxan diabetic rats for 15 days. The hyperglycemic symptoms were observed. The blood glucose, lipid levels and the nephrotic representations were measured. RESULTSWhen alloxan diabetic rats on high-calorie chow were treated with SZ, the hyperglycemic symptoms were improved, the blood lipid levels were improved, the ratio of kidney over body weight and the blood N-acetyl-β-D-glucosaminidase (NAG) activity were lowered. The degree of renal pathological changes was significantly reduced. CONCLUSIONSZ may be useful for treating diabetes and its complications.