Modern medicine shows that islet hypofunction is an important mechanism of diabetes mellitus(D M).By tracing ancient Chinese medicine literature，the authors found that the incidence of diabetes was closely related to spleen and kidney.Qi and yin deficiency is the basis of diabetes islet dysfunction.Phlegm-dampness and blood stasis are pathological products，which are predisposing factors.During treatment， according to Qi and Yin deficiency， yin and yang deficiency， or yang deficiency appearing in four stages of depression，heat，deficiency and loss，drugs can be used in terms of syndrome differentiation.If there are turbid phlegm and blood stasis，blood-activating and stasis-resolving will be used.Invigoration is mainly used in the latent period and the incipient stage of diabetes，while combination method of clearing and nourishing is applied in the typical period.