Striatal D2 dopaminergic receptors of 12 drug-free schizophrenic patients and 12 normal subjects were investigated with positron emission tomography and [76Br]bromospiperone. Patients were classified according to DSM-III criteria, and their clinical symptoms were rated according to Andreasen's negative and positive symptom scales. The ratio of striatal to cerebellar radioactivity was taken as an index of striatal D2 dopamine receptor density. There was no significant difference between the control subjects and the overall schizophrenic group and no significant relationship between this index and the symptom ratings. However, state-dependent variables could partly account for the striatal D2 receptor density variability.