Objective To investigate the effects of Chinese herbal compound formula on plasma endothelin and serum nitric oxide of diabetic rats. Methods The selected SD male rats were induced by streptozotoc (53 mg/kg i.p) and the model rats were divided at random into model contrasted group (MCG), Chinese herbal compound formula treated group (CTG) and ramipri treated group (RTG) while the normal contrasted group (NCG) was set up.CTG were supplied with decoctions of Chinese herbal compound formula, RTG were supplied with solution of ramipri, MCG and NCG were supplied with water. Eight weeks later, the rats were killed and their blood were collected at the same time. Changes of PG, RW/BW, 24 hUAlb, plasma ET, serum NO were observed. Results BG, RW/BW, UAlb, ET and NO of MCG, CTG and RTG were more evidently increased than that of NCG (P