Background: In patients with type 2 diabetes, the presence of microalbuminuria, reflecting a widespread vascular damage, can be a marker of nephropathy, retinophaty and cardiovascular diseases. Aim: To study the relationship between microalbuminuria and the frequency, severity and outcome of retinopathy in patients with type 2 diabetes mellitus. Patients and methods: One hundred patients with type 2 diabetes were subjected to a clinical examination, serial monitoring of blood pressure and quarterly measurement of microalbuminuria by RIA. Annually, a fundoscopy, a color photography of the posterior pole and retinal angiofluorescence were performed. Retinophaty was classified as basal (mild to moderate), preproliferative and proliferative. Sixty four normoalbuminuric patients (urinary albumin of less than 30 mg/24 h) were included in group 1 and 36 patients with a urinary albumin over 30 mg/24 h in group 2. Fifty seven patients with normal blood pressure were randomly treated with enalapril or placebo and those with hypertension received enalapril or acebutolol to normalize blood pressure. Results: Sixty one percent of group 1 patients and 41% of group 2 patients has retinopathy (p < 0.05). The retinal lesions were proliferative in 41% of group 2 patients and in 8% of group 1 patient (p < 0.05). Retinopathy was present in 67% of hypertensive patients of group 2 and in 41% of hypertensive patients of group 1. An unfavorable evolution of retinopathy was observed in 22% of group 2 patients and in 5% of group 1 patient (p < 0.05). Conclusions: In type 2 diabetic patients, the presence of microalbuminuria is a prediction of a higher frequency, severity and dismal evolution of diabetic retinopathy (Rev Méd Chile 2000; 128: 1085-92).