Six equal groups of adult male albino rats were orally administered with three different concentrations (14, 7, 3.5 mg/kg bw.) of carbosulfan technical (88.5%) and Marsal 20% EC Formulation (one conc. of each form per group) for 28 consecutive days, then kept two other weeks without treatment as a recovery period. Samples of brain, thyroid, lung and spleen tissues were taken from all groups at the end of treatment and recovery periods, examined microscopally and compared with control tissues. Results showed that the treatment with technical carbosulfan not affected on thyroid tissues, when affected on brain, lung and spleen tissues, then lung and spleen tissues were repaired after the recovery period but brain tissues still damaged. In case of Marsal 20%EC formulation treatment both thyroid and brain tissues not affected, when both lung and spleen tissues affected and this effect was repaired after the recovery period and the tissues returned to normal state.