Abstract: Objective To study the expression and correlation of Homer and insulin in rats with Type 2 Diabetes mellitus. Methods 22 Diabetes mellitus rats and 15 normal rats were sacrificed, the pancreases of rats were taken to detect Homer (Homerlc, Homer2 and Homer3) and insulin by using Polymerase Chain Reaction (PCR), Immunohistochemistry and double immunofluorescent labeling methods. Results Homerl, Homer2 and Homer3 were positive in the pancreases. In rats with Diabetes mellitus, leverages of insulin were much lower, but expressions of Homer1c, Homer2 and Homer3 protein were much higher. Conclusion The result shows that there is a significant change in the expression of Homer1c, Homer2,Homer3 and insulin between two groups．Homer may play important roles in insulin secretion，Homer1c, Homer2,Homer3 may act as inhibitors.

Key words: Type 2 diabetes mellitus, pancreatic islets, Homer, expression