Glucagon like peptide-1 (GLP-1) receptor agonists (GLP-1RA), exenatide and liraglutide, exert their hypoglycemic effects by enhancing the secretion of insulin, inhibiting the release of glucagon, reducing insulin resistance, suppressing appetite and inhibiting gastric emptying. These effects are in a glucose level-dependent manner so as to prevent severe hypoglycemia. In addition to these definite hypoglycemic effects, the agents also decrease blood pressure, protect heart and blood vessels, attenuate fatty liver and reduce body mass. In animal experiments, these GLP-1RA drugs protect the function of β cells, and are safely combined with metformin, sulfonylureas, thiazolidinediones and insulin in the treatment of diabetes. Exenatide and liraglutide, as representatives of GLP-1RA, are a good option to control blood glucose and reduce body mass for diabetic patients.