Oxidative stress is closely involved in neurodegenerative diseases. The present study aimed to examine the effect of anti-oxidant DHM (dihydromyricetin) on 3NP (3-nitropropionic acid) -induced behavioral deficits of experimental rats and striatal histopathological injury by using behavioral, imaging, biochemistry, histochemistry and molecular biology technologies. The experimental results showed that both motor dysfunctions and learning and memory impairments induced by 3NP were significantly reduced after DHM treatment. 3NP-induced striatal metabolic abnormality was also remarkably improved by DHM treatment, showed as the increased glucose metabolism in PET/CT scan, decreased MDA (malondialdehyde) and increased SOD (superoxide dismutase) activity in enzyme histochemical staining. In addition, the cell apoptosis was evidently detected in the striatum of the 3NP group, while in the 3NP + DHM group, the number of apoptotic cells was remarkably reduced. 3NP treatment obviously induced down-regulation of Bcl-2, and up-regulations of Bax and Cleaved Caspase-3, while these changes were significantly reversed by DHM treatment. The present results suggested that DHM showed its protective effect by anti-oxidant and anti-apoptosis mechanisms.