Nuclear magnetic resonance (NMR) is a special branch of spectroscopy which exploits the magnetic properties of atomic nuclei for molecular elucidation and identification. A technique that was initially developed to analyze chemical and physical molecular structure is now widely used in medical diagnosis. The noninvasiveness, non-destructiveness and simplicity of sample preparation make NMR the preferred technique for metabolomics study. Various body fluids such as urine, saliva, blood, plasma, serum and sweat have been explored to identify potential biomarkers of diseases. Psychiatric disorders, specifically alcohol-use disorder and neurological disorders such as Parkinson’s disease, have been investigated with the aid of NMR spectroscopy. Cancer has been one of the most widely studied areas and the research also includes determination of biomarkers which not only could detect the presence of cancer but also potentially predict the various cancer processes in cancer cell lines. Infectious diseases including the compounds produced by the microorganisms such as in tuberculosis and pneumonia have also been explored. Besides, NMR metabolomics has also been used to establish a metabolic fingerprint for risk stratification and early detection of cardiovascular disease (CVD). The samples of subjects with the diseases were collected and the metabolites were compared against controls such as healthy individuals using complex chemometrics and multivariate data analysis such as principal component analysis, partial least square and orthogonal partial least square analyses to distinguish the potential biomarkers. In terms of the various uses of NMR metabolomics in the subject of diagnostic medicine, more improvements to overcome the analytical limitations are expected, making it one of the most notable diagnostic tools of the future. This chapter reviewed some of the published articles in cancer, psychiatric and neurological diseases to provide examples of using NMR spectroscopy in diagnosing human disorders.