Alzheimer's disease (AD) is a neurodegenerative multifactorial disease whose cause is still unknown. The majority of AD biochemical markers currently available have been developed as an extension of targeted physiological studies on the basis of the amyloid hypothesis. The potential of metabolomics for the discovery of novel biomarkers and elucidation of new biochemical pathways modified in the progression of AD is highlighted in this review work. A variety of nontargeted metabolomic approaches for the discrimination between healthy subjects and AD patients are described. Moreover, the feasibility of metabolomics to predict progression to AD in individuals with mild cognitive impairment is also presented.