Purpose: Successful immunotherapies for IDH mut gliomas require better knowledge of T-cell target antigens. Here, we elucidated their antigen repertoire recognized by spontaneous T-cell responses using an unbiased proteomic approach. Experimental Design: Protein fractionations of tissue lysates from IDH mut gliomas ( n = 4) were performed. Fractions were tested by IFN ELISpot assay for recognition through patients' T cells. Proteins of immunogenic fractions were identified by mass spectrometry and validated by in silico -predicted synthetic long peptides in patients of origin, additional IDH mut glioma patients ( n = 16), and healthy donors ( n = 13). mRNA and protein expression of immunogenic antigens was analyzed in tumor tissues and IDH mut glioma stem-like cells (GSC). HLA-A*02–restricted T-cell epitopes were functionally determined by short peptides and numbers of antigen-specific T cells by HLA-peptide tetramer analysis. Results: A total of 2,897 proteins were identified in immunogenic tumor fractions. Based on a thorough filter process, 79 proteins were selected as potential T-cell antigens. Twenty-six of these were recognized by the patients’ T cells, and five of them (CRKII, CFL1, CNTN1, NME2, and TKT) in up to 56% unrelated IDH mut glioma patients. Most immunogenic tumor-associated antigens (TAA) were expressed in IDH mut gliomas and GSCs, while being almost absent in normal brain tissues. Finally, we identified HLA-A*02–restricted epitopes for CRKII, NME2, and TKT that were recognized by up to 2.82% of antigen-specific peripheral cytotoxic T cells in IDH mut glioma patients. Conclusions: By analyzing the repertoire of T-cell target antigens in IDH mut glioma patients, we identified five novel immunogenic TAAs and confirmed their expression on IDH mut tumors and GSCs. Clin Cancer Res; 24(12); 2951–62. ©2018 AACR .