This study was conducted to examine the hypoglycemic effects of complexcity extract(DB 55) from five oriental medicinal plants on the intake of food, body weight, blood glucose level, insulin content, serum GOP, GPT, BUN and hematocrit value in streptozotocin(STZ)-induced diabetic rats. General nutritional composition was also assessed. Thirty- five male Sprague-Dawley rats were assigned to five groups : normal control group(NC), STZ-diabetic control group (STZ-control), STZ-diabetic DB-1 group(DB 55-1), STZ-diabetic DB-2 group(DB 55-2) and STZ-diabetic DB-3 group(DB 55-3). The animals were fed an experimental diet for 12 weeks. Body weight gain of the STZ-diabetic group was significantly lower but diet intake was significantly higher than the NC group. Blood glucose levels of the DB-1, DB-2 and DB-3 rats were significantly lower than the STZ-control animals. Insulin level of STZ-control rats was lower than the NC serum GOT, GPT and BUN levels were significantly higher in the NC group, but hematocrit value was not significant as compare to the STZ-diabetic group. Blood glucose level was lower observed for the DB 55-1, DB 55-2 and DB 55-3 group. The results will be useful in oriental diet therapy and in the developing functional food resources.