Many traditional plants are used for treatment of diabetes throughout the world as adjuncts to conventional therapy. The purpose of this study was  evaluate the effects of thirteen different plants on arginase, creatin kinase, amylase and lipase activities in serum of diabetic rats. Diabetes was induced in 70 adult male albino rats by intraperitoneal injection of 175 mg/ kg body weight of alloxan. Rats were divided into 14 groups. Thirteen of which consumed a complex of normal pelletes diet supplemented with the amounts, equal to 6.25℅ of their weight with different plants including coriander, walnut leaf, fenugreek, garlic, celery, coriander seed, pomegrenate, lemon, madder, poly- germander, carrot, onion and fumotory for 15 days. An additional group which was diabetic but received no plant diet, was selected as the positive control, and a healthy group was chosen as the negative control. The enzyme activities of the above sera was measured and the results were as follow. No significant difference in arginase or creatine kinase activities were observed among the negative, positive and experimental groups. Amylase activity was significantly lower in positive control group compared to the negative control. The amylase activity in groups which received garlic and carrot was also significantly higher than the positive control (  p<0.05). Lipase activity was significantly increased in the positive control compared to the negative control. This activity was significantly decreased in group which received garlic.