Labeled glucose[6-17O] was used to evaluate differences in glucose metabolism between normal and tumor brain tissue. Experiments were performed using an intracranial 9L glioma model at 21.1 T magnet by observing changes of 17O-water and 17O-glucose MR peaks. The estimated rate of the total glucose metabolism in 9L glioma was approximately 11 times more than in the normal brain. Correspondingly, glucose metabolism rate is 7.5 times more in glioma at the enolase step. 17O MRI/MRS is an encouraging tool for assessing the differences in glucose metabolism in various cancer cells.