Overall survival of gliomas has been reported to be highly associated with the presence of isocitrate dehydrogenase (IDH) and telomerase reverse transcriptase (TERT) promoter mutations. The aim of this study is to define MR spectroscopic (MRS) differences of diffuse glioma subgroups classified by IDH and TERT promoter mutations at 3T. TERT-only mutated and TERT wild type IDH wild type (TW-IDHW) gliomas had similar metabolic profiles. Besides well-reported 2HG, our study indicated the importance of glycine, glutathione, glutamate, and glutamine in identification of IDH-mutant gliomas. TERT-only gliomas had the highest glutamate and glutathione, which might be indicators of poor overall survival.