Background: Intercultural differences influence acute inpatient psychiatric care systems. Aims: To evaluate characteristics of acute inpatient care in a German and a Japanese hospital. Method: Based on a sample of 465 admissions to the Psychiatric State Hospital Regensburg (BKR) and 91 admissions to the Hirakawa Hospital (HH) over a six-month period in 2008, data from the psychiatric basic documentation system (BADO) were analysed with regard to socio-demographic characteristics, treatment processes and outcome indicators. Results: Schizophrenia and related psychosis was the most common diagnosis in both hospitals. Cases at the BKR were admitted more quickly after onset of the present episode. Global Assessment of Psychosocial Functioning (GAF) ratings at admission were lower at the HH. Most admissions to both hospitals received psychopharmacological treatment, but more at the HH received psychotherapy. Length of stay was significantly longer at the HH (75 days) than at the BKR (28 days). Admissions to the HH were more improved with regard to GAF and clinical global impression (CGI). Conclusions: Acute admissions in Germany provide intensive care with short hospitalization as crisis intervention. For acute admissions in Japan, comprehensive care for severe mental illness precedes emergency admissions and achieves greater improvement with longer hospitalization.