Given their therapeutic activity, natural products have been used in traditional medicines throughout the centuries. The growing interest of the scientific community in phytopharmaceuticals, and more recently in marine products, has resulted in a significant number of research efforts towards understanding their effect in the treatment of neurodegenerative diseases, such as Alzheimer's (AD), Parkinson (PD) and Huntington (HD). Several studies have shown that many of the primary and secondary metabolites of plants, marine organisms and others, have high affinities for various brain receptors and may play a crucial role in the treatment of diseases affecting the central nervous system (CNS) in mammalians. Actually, such compounds may act on the brain receptors either by agonism, antagonism, allosteric modulation or other type of activity aimed at enhancing a certain effect. The current manuscript comprehensively reviews the state of the art on the interactions between natural compounds and brain receptors. This information is of foremost importance when it is intended to investigate and develop cutting-edge drugs, more effective and with alternative mechanisms of action to the conventional drugs presently used for the treatment of neurodegenerative diseases. Thus, we reviewed the effect of 173 natural products on neurotransmitter receptors, diabetes related receptors, neurotrophic factor related receptors, immune system related receptors, oxidative stress related receptors, transcription factors regulating gene expression related receptors and blood-brain barrier receptors., The author A.R.S. is grateful to the authors C.G. and J.M.R for the scientific assistance and suggestions shared throughout the supervision of her B.Sc. final project. The author A.R.S. also acknowledges the Department of Biology (DB) and the Centro de Biologia Molecular e Ambiental [Centre of Molecular and Environmental Biology] (CBMA) from School of Sciences (EC), University of Minho (UM), Braga, Portugal, by providing all the conditions leading to the B.Sc. in Biochemistry. The corresponding author C.G. is grateful to Fundação para a Ciência e a Tecnologia [Foundation for Science and Technology, FCT I.P.] (FCT I.P.) for the FCT Investigator (IF/01332/2014/CP1255/CT0001). The author J.M.R. acknowledges the CBMA and the Instituto de Ciência e Inovação para a Biosustentabilidade [Institute of Science and Innovation for Biosustainability] (IBS) from University of Minho (UM), Braga, Portugal, where he recently carried out his activities as invited assistant researcher and professor. The author J.M.R. is also grateful to the Laboratório Associado para a Química Verde (LAQV) [Green Chemistry Laboratory] from REQUIMTE – Rede de Química e Tecnologia [REQUIMTE – Chemistry and Technology Network], as well as to the Department of Chemistry and Biochemistry (DCB) from the Faculty of Sciences from University of Porto (FCUP), Porto, Portugal, where he is currently researcher. Regarding to the author J.M.R., this work was supported by the strategic programmes UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) (Research project entitled “EcoAgriFood: Innovative green products and processes to promote Agri-Food BioEconomy”) and PTDC/SAUNUT/30448/2017 (POCI-01-0145-FEDER-030448) (Research project entitled “Poly4CD: Action of Dietary Polyphenols in Preventing Celiac Disease”) funded by Portuguese national funds through Fundação para a Ciência e Tecnologia [Foundation for Science and Technology] (FCT-I.P.)/Ministério da Ciência, Tecnologia e Ensino Superior [Ministry of Science, Technology and Higher Education] (MCTES), and Fundo Europeu de Desenvolvimento Regional [European Regional Development Fund] (FEDER), under the scope of the COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI) [COMPETE2020 – Competitiveness and Internationalization Operational Program] and by COST Action 18101 “SOURDOMICS”, supported by COST (European Cooperation in Science and Technology). C. G. and C. D.-M. are grateful for the financial support from FCT/MCTES through national funds (UID/QUI/50006/2019). C. G. and C. D.-M. would also like to thank the EU and FCT for funding through the projects: DESignBIOtecHealth - New Technologies for three Health Challenges of Modern Societies: Diabetes, Drug Abuse and Kidney Diseases (Portugal2020, Norte-01-0145-FEDER-000024) and project PTDC/OCE-ETA/30240/2017- SilverBrain - From sea to brain: Green neuroprotective extracts for nanoencapsulation and functional food production (POCI-01-0145-FEDER-030240); and to the REQUIMTE for the project “Sea_4_Brain_Food”. All the authors acknowledge the CBMA and IB-S by the financial support provided specifically for this open access publication.