Magnetic resonance spectroscopy (MRS), that may be added to conventional magnetic resonance imaging (MRI) exam exhibit an increasing role in the management of brain tumors. These technique allow quantitative analysis of metabolites, either cell specific, either reflecting physiological and/or pathological process. With a rigorous approach, MRS explore brain metabolism that may improve MRI data in clinical practice in neuro-oncology. Positive diagnosis of brain tumor, differential diagnosis between infiltrative glioma (grade II) and gliomatosis, determination of the limits of tumor infiltration, and distinction between tumor and post-therapeutic images are some of the potential applications of MRS. Ongoing and future studies may also precise the place of MRS in the differential diagnosis between high grade glioma, metastasis and CNS lymphoma, as well as in monitoring therapy in glioma.