We report on an incidental detection of a meningioma on [F]-2'-fluoro-5-methyl-1-beta-D-arabinofuranosyluracil (F-FMAU) PET/CT scan that was performed during a prospective investigation of F-FMAU PET/CT for targeted biopsy of potential sites of tumor in men with suspected prostate cancer based on elevated prostate-specific antigen level. Neither prostate multiparamteric MRI nor F-FMAU PET/CT localized small volume Gleason 3 + 3 tumor deposits. However, an incidental focal high accumulation of F-FMAU was observed in high right parietal lobe that displayed characteristics of a meningioma on a subsequent brain MRI.