Oxidative stress on dopaminergic neurons in the substantia nigra caused by cytotoxic free radicles generated during oxidative metabolism of dopamine is hypothesized to be one of the etiopathogenic mechanisms of Parkinson’s disease (PD). Glutathione peroxidase (GPX) plays an important role in reducing peroxide–mediated stress. Selenium, a trace element, is a component of GPX and assists in this process. The aim of this case–control study was to analyze serum Selenium levels among PD patients in central Kerala. Serum selenium was estimated using Inductively Coupled Plasma–Mass Spectrometry in 30 patients and 30 controls. Serum Selenium levels were found to be elevated in PD patients as compared to controls.