We studied cerebral glucose metabolism, using Positron Emission Tomography (PET) and (F-18) fluorodeoxyglucose, in 15 young schizophrenic patients compare to 15 age-matched healthy volunteers. The PET investigation was made in a quiet room with a dimly light. Each subject remained in a supine resting state with eyes closed. Results failed to demonstrate any differences in glucose utilization between schizophrenic patients and control subjects, as far as absolute or relative, left and right values are concerned. Besides, variability of metabolic values was significantly higher in schizophrenics than in controls.