Oxidative stress contributes to the cascade, leading to dopamine cell degeneration in Parkinson's dis-ease (PD). However, oxidative stress is intimately linked to other components of the degenerative proc-ess, such as mitochondrial dysfunction, excitotoxicity, nitric oxide toxicity and inflammation. It is therefore difficult to determine whether oxidative stress leads to, or is a consequence of, these events. Oxidative stress was assessed by estimating lipid peroxidation [LPO] product in the form of thiobarbi-turic acid reactive substances [TBARS], and nitric oxide. Enzymatic antioxidants like superoxide dis-mutase [SOD], glutathione peroxidase [GSHpx], catalase, ceruloplasmin and non enzymatic antioxi-dant vitamins e.g. vitamin E,C in either serum or plasma or erythrocyte in 22 patients of Parkinson's disease [PD] in the age group 45-75 years. Trace elements e.g. copper, zinc and selenium were also es-timated. Plasma TBARS and nitric oxide levels were Significantly high but activity of SOD, GSHpx, catalase, and levels of ceruloplasmin, vitamin-E, vitamin-C, copper, zinc and selenium were signifi-cantly low in Parkinson's disease when compared with control groups. Present study showed that im-balance between free radicals and antioxidants may be playing a role in dopaminergic neuronal loss in substentia nigra pars compacta and involved in pathogenesis of the Parkinson's disease.