_____________________________________________________________________________________________________ *Corresponding author: E-mail: ayman.elsamanoudy@gmail.com; International Journal of Biochemistry Research & Review 29(8): 26-41, 2020; Article no.IJBCRR.59525 ISSN: 2231-086X, NLM ID: 101654445 The Potential Use of Blood, Cerebrospinal Fluid, Saliva and Urine as Biological Samples for the Diagnosis of Alzheimer’s Disease Adnan Awn Algarni 1 , Abdulhadi I. Bima 1 and Ayman Z. Elsamanoudy 1,2* 1 Department of Clinical Biochemistry, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia. 2 Medical Biochemistry and Molecular Biology, Faculty of Medicine, Mansoura University, Mansoura, Egypt. Authors’ contributions This work was carried out in collaboration among all authors. Author AZE designed the study, wrote the protocol, managed the literature searches, edited the manuscript and supervised the work. Author AAA collected data and wrote the first draft of the manuscript. Authors AZE and AIB revised the manuscript. All authors read and approved the final manuscript. Article Information DOI: 10.9734/IJBCRR/2020/v29i830210 Editor(s): (1) Dr. Chunying Li, Georgia State University, USA. Reviewers: (1) Grace O. Isehunwa, University of Ibadan, Nigeria. (2) Bhoopendra Singh, Jamia Hamdard University, India. Complete Peer review History: http://www.sdiarticle4.com/review-history/59525 Received 24 May 2020 Accepted 31 July 2020 Published 03 August 2020 ABSTRACT Background and Aim: Alzheimer’s disease (AD) is the most common cause of dementia. 80% of all dementia is due to AD. Diagnosis of AD is a difficult task, as the accurate diagnosis requires post-mortem examination of brain autopsy samples. Diagnosis of AD in living individuals can be aided by the establishment of the clinical criteria, positron emission tomography (PET) examination, and biomarkers. The study of biomarkers for diagnosis of AD could help clinicians to evaluate individuals at risk, and confirm the occurrence as well as the progression of AD in a non-invasive manner. High sensitivity and high specificity of the used markers are mandatory criteria for these biomarkers to trusted for AD diagnosis and prognosis. So, this review article aims to focus on the potential use of body fluids as a source of the biomarkers that are used for investigating patients with AD. Methodology: In the current study, we reviewed scientific articles that discuss AD pathogenesis and diagnosis of Google Scholar database, Pubmed, Pubmed Central, Cochrane Database of Review Article