Objectives: To prove the channel-tropism theory in herbology, we investigated the anti-diabetic effect of six herbal plants used for lower wasting-thirst in streptozotocin-induced diabetic rats. Methods: Diabetes was induced in male Sprague-Dawley rats by consecutive injection of streptozotocin (30 mg/kg i.p.) for 5 days. The rats were divided into normal control, diabetic control, and diabetic treatment with Lycii Radicis Cortex (LRC, 300 ㎎/㎏); Corni Fructus (CF, 300 ㎎/㎏); Bombyx Batryticatus (BB, 50 ㎎/㎏); Lycii Fructus (LF, 300 ㎎/㎏); Phellodendri Cortex (PC, 300 ㎎/㎏); Epimedii Herba (EH, 300 ㎎/㎏); and glibenclimide (10 ㎎/㎏) as a reference drug. Herbal extracts or reference drug were administered orally for 28 days. The changes of body weight, food intake and water intake, and serological markers such as blood glucose, serum total cholesterol, triglyceride (TG), blood urea nitrogen (BUN), and creatinine (Cr) were measured. Results: The decrease of body weight and the increase of food and water intake in STZ-induced diabetic rats was improved by the administration of CF and LF. Also, the enhancement of blood glucose and serum total cholesterol, TG, BUN and Cr in STZ-induced diabetic rats was significantly inhibited by the administration of CF, BB, LF and glibenclimide. On the other hand, EH strongly inhibited the increase of BUN and Cr in the sera of STZ-induced diabetic rats. Conclusions: These results suggest that among six herbal medicines used lower emaciation of emaciation-thirst disease, CF, BB, LF and EH show a characteristics including the channel-tropism theory.