To explore anti-diabetic effect of Difuye extract from water on diabetic mice model. Methods:Alloxan-induced diabetes mice with similar glucose values were selected, and given test extract for respectively 10 and 7 days, observed glucose values; carried out statistic analysis; and performed toxic experiment. Results:Anti-diabetic effect was shown after the extract was given 4.0g/kg intragastrically for 7-10 days, which was about 20% decrease, and 20% at most compared with glucose values of the control group. Conclusion: Difuye extract from water has definite anti-diabetic effect and no obvious side effects.