Objective To investigate the effects of sodium selenite on morphology of substantia nigra % dopamine content in striatum and blood level of Parkinsons Disease (PD) model rats. Methods 8 rats were selected as the control group (group I). The remaining 40 rats were injected with MPTP for 7 days to establish PD model, 24 PD rats were randomly divided into MPTP group ( R group) , MPTP+ 0. 05 mg/kg Se group (皿 group) , MPTP+ 0. 1 mg/kg Se group (IV group) , 8 rats in each group. Group III and group IV were given different doses of sodium selenite for 30 days. Morphological changes of DA neurons in substantia nigra were observed by Nissl staining and TUNEL, and dopa mine content in striatum was detected by ELISA. The changes of blood indexes in each group were detected by blood routine and blood biochemistry. Results Compared with group I, the number of Nissl bodies in group II decreased signif icantly, the number of apoptotic cells in substantia nigra increased significantly (P<0. 05). The content of DA in stria turn decreased significantly (P<0. 05), DBIL was significantly decreased? WBC? Neu? Lym, Mon and UA were signifi cantly increase (P<0. 05). Compared with group II? the number of Nissl bodies ? the number of apoptotic cells and the content of DA in group III increased significantly (P<0. 05), The contents of TP, ALB, AST? CHOL, Urea and UA decreased significantly (P<0. 05) , while the contents of HGB, ALP and GLU increased significantly (P<0. 05). In group IV, the number of Nissl bodies recovered, the number of apoptotic cells decreased and the content of DA increased, but the difference was not significant. The contents of ALB and Urea in group IV decreased significantly (P< 0. 05), Conclusion Sodium selenite at the dose of 0. 05mg/kg can alleviate neuron degeneration in PD rats, inhibit the reduction of DA content, and have a significant impact on liver function, kidney function? blood glucose and other indica tors in PD rats.