The expression of MAGE tumor rejection antigens in brain tumors is unclear. We investigated the expression of MAGE-1 and-4 proteins in brain tumors with antibodies to recombinant MAGE-1 and -4 proteins. MAGE-1 or -4 protein was detected in a majority (12 of 14) or some (5 of 14) of gliomas, respectively, by the immunoblot analysis. In contrast, MAGE-1 or -4 protein was rarely detected in the non-glioma tumors (3 of 14 or 1 of 14, respectively). Cellular MAGE-1 protein was detected in the cytoplasma of the glioblastoma cells with immunohistochemical staining. The expression of the MAGE-4 protein was confirmed by enzyme-linked immunosorbent assay. The results suggest that the MAGE-1 protein is an appropriate target molecule for specific immunotherapy of glioma.