Introduction: Thrimethyltin (TMT), an environmental toxicant, induces selective neuronal death in the central nervous system (CNS) of human and rodents. It has been suggested that Lithium Chloride (LiCl) may prevent TMT toxicity and its consequent neuronal death. This study examined neuroprotective effects of LiCl on cerebellar granular cells in lobule V and VI of TMT-intoxicated Sprague Dawley rats. Materials and Methods: 30 adult male rats were divided into three groups. The control group (untreated healthy rats) did not receive any treatment the sham group received saline for fourteen days, after TMT (8 mg/kg body weight) intoxication. The experimental group received LiCl (20 mg/kg body weight) for fourteen days after TMT intoxication. The rats were sacrificed and histopathological assessments were performed. Results: Data indicated that the density of granular cells in the cerebellar folium V was significantly higher in sham rats compared to control and experimental groups. Administration of LiCl did not affect the density of granular cells in folium V of the cerebellum. Furthermore, the results showed that the density of granular cells in the folium VI was significantly reduced in the sham group, compared to the other groups. Administration of LiCl prevented neuronal apoptosis and preserved granular cells in the cerebellum. Conclusion: This study suggests that LiCl may have a neuroprotective effect on toxic damage of TMT in the cerebellum.