Neurochemicals such as dopamine (DA) and serotonin (S-HT) are linked to disorders such as Parkinson’s disease, epilepsy, addiction and many others. Detection of and monitoring these neurochemicals in vivo and in vitro has become important in treating various disorders. The electroactive nature of DA and S-HT has enabled employing electrochemical techniques to detect them at low concentrations, and a variety of electrodes and approaches have been reported. The use of nanomaterials such as carbon nanotubes, graphene and nanowires has been advocated in recent years for the sensitive detection of neurochemicals. This article reviews the advances in nano biosensors for this application and discusses the future outlook and challenges.