Chronic Hallucinatory Psychosis (CHP) is typically a French disease entity initially described by G Ballet (1911) and whose diagnostic criteria were established by Pull (1987). This diagnosis is not used in English and German literature. The aim of this study was to investigate the relationship between Pull's criteria for CHP and the criteria for schizophrenia defined by 14 different diagnostic systems and schizoaffective disorders. Seventy-two non-affective psychotic patients (34 men, 38 women), aged 20 to 84, in exacerbated or stabilized phase, were interviewed by the same investigator (SD). The patient distribution between the diagnoses in the different diagnostic systems was carried out using a computerized 208-item checklist. The main results indicated that the definite CHP diagnosis was significantly related to the Catego S + (C = 0.52; P < 0.01), New-Haven, (C = 0.40; P < 0.05) and Schneider (C = 0.54; P < 0.001) systems for schizophrenia and with the depressive-schizoaffective disorder (C =0.39; P < 0.05) in the RDC system. The probable CHP diagnosis was significantly linked with the same systems and with the probable RDC (C = 0.39; P < 0.05) for schizophrenia. These results emphasize that in 13 out of the 14 diagnostic systems, schizophrenic and schizoaffective disorders overlapped with CHP in the French diagnostic system. Among these systems, four schizophrenic diagnoses were significantly linked to CHP. In contrast, the Bleuler system for schizophrenia was not related to CHP at all.