The paper presents the results of a study of the serum levels of monocyte chemoattractant protein-1 (MCP-1) and vascular endothelial growth factor (VEGF) in 120 patients with types 1 and 2 diabetes mellitus complicated by diabetic retinopathy. All the patients with diabetes have been ascertained to show a rise in the levels of MCP-1 and VEGF. Calculation of VEGF/MCP-1 ratio is proposed to evaluate vascular bed lesion in diabetic patients.