This study was designed to elucidate psychiatric admission rates for native Swedes and foreign-born individuals during the period 1991–1994, when Sweden had a great influx of refugees. During the same period, and even earlier, psychiatric in-patient care had been reduced. Tests of differences between Swedes and foreign-born individuals in first psychiatric admission rates were performed using Poisson regressions, and the risk of a readmission was assessed using a proportional hazard model. Foreign-born individuals and native Swedes, both males and females, showed a similar admission pattern with regard to the number of admissions. Foreign-born males under 55 years of age and foreign-born females under 35 years of age had significantly higher admission rates than native Swedes. In total, native Swedes, both males and females, were hospitalized for a significantly longer period than the foreign-born subjects. About 43% of the patients were readmitted. The risk of a readmission was significantly increased among those with a high rate of internal migration. The high admission rates for young foreign-born individuals might be explained by a high incidence of mental illness owing to the trauma of being violently forced to migrate, acculturation difficulties, or unsatisfactory social circumstances such as high unemployment. The shorter hospitalization time could be due to undertreatment or less serious mental illness.