Choroid plexus calcification (CPC) was measured on computed tomography (CT) scans of 87 schizophrenics and 46 controls divided into age subgroups. We studied the relationship between presence and size of CPC and age in both groups, whilst in the schizophrenic group we also investigated the possible correlation between CPC size and age of onset and duration of illness, duration of formal education, psychopathological features of the illness as well as some neuroradiological brain measures. CPC size correlated with age in healthy controls but not in schizophrenics. In the schizophrenic group, left choroid plexus calcification size correlated with the Scale for the Assessment of Positive Symptoms (SAPS) subscales scores of 'formal thought disorder' whilst right choroid plexus calcification size correlated with the ventricular brain ratio at frontal horns (VBRFH). The data are not conclusive, but a possible correlation with a dysgenetic or functional 5-HT alteration can be hypothesized.