The aim of this study was to determine the effect of endurance training on some metabolic parameters of Nicotinamide and Streptozotocin induced type 2 diabetic rats. After the induction of diabetes (injection of Nicotinamide and Streptozotocin), 24 non-obese adult male rats were divided into 3 groups: non-diabetic (n=8), trained diabetic (n=8) and control diabetic (n=8). 4 weeks after the development of diabetes, the trained diabetic group ran on a treadmill for 4 weeks. At the end of the training, intraperitoneal glucose tolerance test was performed to determine insulin sensitivity. Plasma glucose and insulin levels were measured and HOMA-IR was calculated. Independent t test and two-way ANOVA were used to analyze data. Results indicated that during 4 weeks of diabetes induction, an insignificant difference was found in body weight, food intake and fasting plasma insulin level between diabetic and non-diabetic groups, but fasting and non-fasting blood glucose level significantly increased in diabetic group compared with non-diabetic group. After 4 weeks of training, an insignificant difference was found in body weight and food intake among non-diabetic, trained diabetic and control diabetic groups, but training significantly decreased fasting plasma glucose level and HOMA-IR and significantly increased fasting plasma insulin and glucose tolerance in trained diabetic group compared with control diabetic group. Therefore, it appears that 4 weeks of endurance training had beneficial effects on some metabolic parameters of type 2 diabetic rats.