AbstractMucuna pruriens possesses significantly higher antiparkinson activity compared with levodopa in the 6‐hydroxydopamine (6‐OHDA) lesioned rat model of Parkinson's disease. The present study evaluated the neurorestorative effect of Mucuna pruriens cotyledon powder on the nigrostriatal tract of 6‐OHDA lesioned rats. Mucuna pruriens cotyledon powder significantly increased the brain mitochondrial complex‐I activity but did not affect the total monoamine oxidase activity (in vitro). Unlike synthetic levodopa treatment, Mucuna pruriens cotyledon powder treatment significantly restored the endogenous levodopa, dopamine, norepinephrine and serotonin content in the substantia nigra. Nicotine adenine dinucleotide (NADH) and coenzyme Q‐10, that are shown to have a therapeutic benefit in Parkinson's disease, were present in the Mucuna pruriens cotyledon powder. Earlier studies showed that Mucuna pruriens treatment controls the symptoms of Parkinson's disease. This additional finding of a neurorestorative benefit by Mucuna pruriens cotyledon powder on the degenerating dopaminergic neurons in the substantia nigra may be due to increased complex‐I activity and the presence of NADH and coenzyme Q‐10. Copyright © 2004 John Wiley & Sons, Ltd.