Abstract Purpose To evaluate the accuracy of 1 H‐MR spectroscopy ( 1 H‐MRS) as an intervention limiting diagnostic tool for glioblastoma multiforme. GBM is the most common and aggressive primary brain tumor, with mean survival under a year. Oncological practice currently requires histopathological diagnosis before radiotherapy. Materials and Methods Eighty‐nine patients had clinical computed tomography (CT) and MR imaging and 1.5T SV SE 1 H‐MRS with PRESS localization for neuroradiological diagnosis and tumor classification with spectroscopic and automated pattern recognition analysis (TE 30 ms, TR 2000 ms, spectral width 2500 Hz and 2048 data points, 128–256 signal averages were acquired, depending on voxel size (8 cm 3 to 4 cm 3 ). Eighteen patients from a cohort of 89 underwent stereotactic biopsy. Results The 18 stereotactic biopsies revealed 14 GBM, 2 grade II astrocytomas, 1 lymphoma, and 1 anaplastic astrocytoma. All 14 biopsied GBMs were diagnosed as GBM by a protocol combining an individual radiologist and an automated spectral pattern recognition program. Conclusion In patients undergoing stereotactic biopsy combined neuroradiological and spectroscopic evaluation diagnoses GBM with accuracy that could replace the need for biopsy. We do not advocate the replacement of biopsy in all patients; instead our data suggest a specific intervention limiting role for the use of 1 H‐MRS in brain tumor diagnosis. J. Magn. Reson. Imaging 2010;32:1038–1044. © 2010 Wiley‐Liss, Inc.