Angiogenesis is a key mechanism that influences several physiological and pathological processes, including wound healing. During the past decades, many groups have shown that controlling angiogenesis might be an answer to overcome pathological situations when this process is out of control. Many altered metabolic states exert considerable influence on the development of angiogenesis. We have chosen diabetes as a model of a progressive metabolic disease with many associated conditions, including an alteration of wound healing dynamics described elsewhere. To evaluate the growth of newly formed blood vessels during diabetes, we induced corneal angiogenesis through silver nitrate cauterization in streptozotocin-induced diabetic rats, always comparing to control non-diabetic or insulin-treated diabetic rats. Computer-aided analysis showed that both the percentage of area taken by vessels on the cornea and their average length were decreased in diabetic animals; furthermore, this diminishment was prevented by insulin treatment in previously diabetic rats. Immunohistochemical staining of neutrophils and macrophages (EDI clone) did not show any differences on number of migrating cells in the cornea. Immunolocalization of vascular endothelial growth factor and basic fibroblast growth factor did not differ considerably among groups either. These results support previous findings that angiogenesis is decreased due to the development of diabetes mellitus but contrasts to descriptions from other investigators in regard to the inflammatory infiltrate and production of growth factors. In our experimental conditions, the cause of the decreased angiogenesis in diabetic rats remains for further elucidation.