Neurofilament light chain (NfL) has been classified as one of the most prominent biomarkers for identification of Parkinson's disease that is manifested by loss of dopaminergic neurons in the gray matter of the brain with the formation of cytoplasmic inclusion bodies in the brain tissue. Novel biosensors are needed for diagnosis of Parkinson's disease as well as monitoring of the treatment process. So, the concentration of NfL in cerebrospinal fluid has been reported to be useful in distinguishing Parkinson's disease from atypical Parkinson's syndromes. For this purpose, an electrochemical immunoaffinity biosensor having limit of detection (LOD), and limit of quantitation (LOQ) as 5.21 ng/L and 15.79 ng/L has been developed for the determination of NfL concentration. In this study, glycidyl methacrylate (GMA) functional monomer was used to form thin polymeric films on the electrode surface and the anti-NfL antibody was immobilized via covalent linkage with GMA as a biorecognition agent.