71 Japanese patients, who were diagnosed as a schizoaffective psychosis (ICD-295.7) and admitted in the year of 1979 in the department of psychiatry of Nagoya City University Hospital and psychiatric ward of its branch hospital, were investigated on the following clinical features: Age of the first psychotic manifestation, heredity, premorbid personality, situation of manifestations, symptomatology, clinical course, somatic complications, EEG-findings and sorts of treatments. This group then was compared statistically with 71 German patients with schizoaffective psychoses, who were admitted in the year of 1980 in the psychiatric department of Munich University Hospital. The statistical differences between these two groups revealed mainly in their symptomatology, not in the other clinical features mentioned above exept a certain type of the premorbid personality and a certain situation of falling ill. As for the delusions, the delusion of reference was very commonly found among the Japanese group, but relatively few in the German (p less than 0,01). On the other hand, the delusion of guilt was much frequent among the German, but extremely rare in the Japanese (p less than 0,001). The depressive symptoms were more frequently seen in the German (p less than 0,001), whereas the catatonic symptomes were more commonly found in the Japanese. Delusion of possession was seen in the Japanese group exclusively. On the premorbid personality-types, the trait of the sensitive personality was more frequently found in the Japanese (p less than 0,05), however, when considering the situations of the manifestations, the inner familial conflicts were found much fewer in the Japanese (p less than 0,05).(ABSTRACT TRUNCATED AT 250 WORDS)