ObjectiveTo compare the results of controlled- release glipizide and immediate-re- lease glipizide in treating type 2 diabetes mellitus.Methods22 patients took controlled-release glipi- zide as treating group, 20 took immediate-release glipizide as compared. The glucose tolerance, insulin, C- peptide and HbA1c were measured before and after treatment. ResultsBoth of controlled-release glipizide and immediate-release glipizide had good results for controlling blood sugar, but controlled-re- lease glipizide did not increase insulin and C-peptide level. Conclusion The controlled-release glipizide had safe and reliable results for controlling blood sugar and decreasing insulin resistence.