Experimental models are important in diabetes mellitus research. The effect of intraperitoneal inoculation of streptozotocin at a dose of 60 mg/kg was evaluated in young male Wistar rats. An experimental study was carried out using 30 male Wistar rats distributed in three groups of 10 rats each, determining biochemical parameters periodically and morphohistological characteristics of organs at 60 days of trial duration. Results. On one day the rats inoculated with streptozotocin became diabetic, showing a correlation with uric acid and bilirubin at all times when measurements were taken, unlike albumin which did not vary at any time. Histological alterations were found in pancreas, liver and kidney, atrophic and without signs of necrosis.