Abstract: The factors affected content stability and the hypoglycaemic activity of Cyclocarya paliurus capsule were examined in this paper.The content stability of Cyclocarya paliurus capsule was evaluated by measuring the values of moisture content, bulk density and angle of repose.Diabetes was induced in mice by using streptozotocin (STZ) , diabetic mice were randomly divided into model control, normal control, positive control and low, medium and high-dose Cyclocarya paliurus capsule treatment groups.After feeding for 3 weeks, several physiological indexes were measured, and histopathological examination of mouse pancreas was observed.The results showed the values of moisture content, bulk density and angle of repose were all in the ideal range.Compared with model control, high-dose Cyclocarya paliurus capsule not only significantly reduced (p < 0.01) blood glucose and total cholesterol levels, improved body weight and hepatic glycogen levels in diabetic mice, but also increased the number and area of islet cell, promoted the recovery of islet cell necrosis.Cyclocarya paliurus capsule present better content stability and had therapeutic effects on diabetic mice induced by STZ.