Childhood parental loss has been associated with a number of psychiatric disorders in adulthood. The present article aims to examine, firstly, the etiologic relationship between early parental loss and later development of schizophrenia and, secondly, the pathoplastic effect of the former on the symptomatology of the latter. We have administered semi-structured interviews inquiring into psychopathology and early separation experiences to a representative sample of first-visit patients to the 31 hospitals and clinics all over Japan (n=1963) and also to a community sample in a small city in Japan (n=218). When 225 patients diagnosed with schizophrenia according to DSM-III-R criteria were compared with 122 healthy control subjects without any lifetime psychiatric disorder, controlled for sex and age, there was no statistically significant difference in the rates of childhood parental loss (death or separation). As regards the pathoplastic effects, it was found that schizophrenic men were less likely to present with negative symptoms if they had experienced separation from the father, and were more likely to show panic attacks if they had experienced separation from the mother. Schizophrenic women were more likely to present with hallucinations if they had suffered any loss of the father. Childhood parental loss is not pathogenic of schizophrenia but appears to exert some pathoplastic influences on its presenting symptoms.