Objective To investigate the effect of liraglutide combined with insulin on the HbA1c, T lymphocyte subsets and islet function in patients with type 1 diabetes.Methods 46 cases from endocrinology department of Tangshan Traditional Chinese Medicine Hospital with type 1 diabetes were selected and randomly divided into two groups each group had 23 patients.Control group were given recombinant human insulin to control blood sugar according to the blood glucose level, and experimental group were given liraglutide on the basis of control group.HbA1c, T lymphocyte subsets, C-Peptide ( CP) and islet function were compared after treatment.ResuIts Compared with control group after treatment, HBAlc level in experimental group was lower (P<0.05); CD4 +T was higher, CD8 +T was lower, and CD4 +/CD8 +T was higher (P<0.05); the fasting plasma glucose (FPG) level was lower (P<0.05);2-hour postprandial blood glucose (2 hPG) was lower (P<0.05); CP and 2-hour postprandial C-Peptide (2 hCP) were higher (P<0.05).There was no significant difference in liver and kidney function between two groups.ConcIusion Liraglutide combined with insulin could significantly reduce serum glycated hemoglobin level, increase CD4 +T level and reduce CD8 +T level, improve islet function in patients with type 1 diabetic.