Manganese is a naturally occurring element and an essential nutrient. It is an essential trace metal that is involved in bone formation, brain development and in the metabolism of carbohydrates, cholesterol and amino acids. Excessive exposure of humans to manganese can result in a neurologic and psychological disorder called Manganism. This study assesses the effect of Manganese on the cerebellar cortex of adult wistar rats. Thirty-six (36) adult wistar rats were picked at random and divided into 4 groups with 9 animals each. Group A which was the control received distilled water, group B, group C and Group D received orally 0.3 mg/kg, 0.6 mg/kg and 0.8 mg/kg body weight of Manganese Chloride respectively for 29 days. Experimental Animals were sacrificed on the 30th day by cervical dislocation. The cerebellum were collected after sacrifice, weighted and fixed in 10% formol calcium and subsequently processed for histological observation using Hematoxylin and Eosin staining principle. Part of the cerebella cortex was homogenized for MDA, NO and SDH analysis. The result shows that the mean body weights decreased significantly in the manganese- treated groups when compared to the control. The mean brain weight of the Manganese Chloride treated groups B, C and D Insignificantly Increased compared with the control. Biochemical analysis of the MDA (Lipid Peroxide), NO (Nitric Oxide) and SDH (Succinate Dehydrogenase) Increased Significantly (P<0.05) in the Manganese treated group compare with the control. Histological analysis showed loss and degenerated neurons particularly the Purkinje cells in the cortical layers of the Manganese treated groups compare with normal Cerebella histoarchitecture in the control. This study concluded that Wistar rats treated with Manganese Chloride demonstrated neurodegenerative changes in the cerebella cortical layers, which may adversely affect some cerebella functions in the Wistar rats investigated.