Objective To observe the changes in the number and activity of endothelial progenitor cell (EPC) from peripheral blood in patients with diabetic retinopathy (DR). Methods Twelve patients with DR (DR group), 18 patients with diabetic mellitus (DM) without DR (DM group), and 15 patients with age-related cataract without DM (control group) were enrolled in this study. Peripheral blood mononuclear cells were isolated by density gradient centrifugation. After 10 days culture, positive rate of EPC was counted by flow cytometry, proliferation, adhesion and migration activities were assayed by MTT chromatometry, adhesion activity assay essay and Transwell assay. Results Flow cytometric test showed that positive rate of EPC in patients of DR group, DM group and control group was (37.370plusmn;2.501)%, (30.130plusmn;3.245)% and (45.190plusmn;1.287)%. There was a significant difference between these three groups (F=27.690, P=0.001). MTT chromatometry showed that A-values of DR group, DM group and control group were 0.330plusmn;0.047, 0.225plusmn;0.042 and 0.120plusmn;0.029. There was a significant difference between these three groups(F=29.327，P=0.000). Adhesion activity assay essay showed that EPC numbers in DR group, DM group and control group were 76.400plusmn;7.503, 51.167plusmn;6.646 and 26.500plusmn;7.853. There was a significant difference between these three groups (F=56.612, P=0.000). Transwell assay showed that EPC numbers in DR group, DM group and control group were 23.600plusmn;6.504, 20.833plusmn;4.491 and 12.000plusmn;2.944. There was a significant difference between these three groups (F=6.477, P=0.012). Conclusion EPC from peripheral blood in patients with DR exhibit reduced numbers and impaired proliferation, adhesion and migration activity.