Disclosure of microalbuminuria gives a hope to improve renal and perhaps cardiovascular outcome of diabetes mellitus by the mean of an early treatment. We studied in 30 diabetic patients for each sex, consecutively admitted to hospital the efficacy of a colorimetric tablet-test for quick screening of microalbuminuria. The results obtained from a 24 hours-urine collection are compared to those observed with a reference radio-immunologic method. In this population whose prevalence for microalbuminuria over 15 micrograms/mn is 30%, the test shows a sensibility and a negative predictive value of 100%, but a specificity and a positive predictive value of about 40%. Else, intensity of positivity follows systolic blood pressure and creatininemia increase. If the good and cheap screening value of the test can be acknowledged, its positivity needs however a precise evaluation by a reference assay before therapeutic decision.