To explore the distribution regularity of TCM syndromes in type 2 diabetes and its pathogenesis. Methods:After going through the clinical charts of admitted patients in Dongzhimen Hospital Affiliated to Beijing University of Chinese Medicine from year 2003 to year 2010, 2735 cases diagnosed as type 2 diabetes were selected to analyze frequency of TCM disease and syndrome, so as to obtain the distribution regularity and relevant factors. Conclusion: The syndrome distribution of type 2 diabetes were qi deficiency, yin deficiency, fire heat, and blood stasis. The blood stasis in patients without complications was slighter than those with complications. The “vigorous fire consuming qi” and “heat hurting Qi- Yin’ may be the key causes to the onset of type 2 diabetes.