The benefit of single-family treatment (SFT) in addition to short educational sessions (SES) consisting of multiple-family treatment was investigated. The study design was a randomized controlled study. Subjects were 30 patients suffering from schizophrenia with at least one of their family members showing high expressed emotion (EE) in the Camberwell Family Interview. After the SES, the patients were randomly allocated to two groups: those who received routine individual outpatient treatment and those who received additional SFT and routine treatment. The two groups were followed for 9 months after discharge, and the relapse risks were compared. The relapse risk was lower in the SES+SFT group than in the SES group (23.1% vs. 35.3%). However, the difference was not significant. When high-EE families were classified into those with many critical comments (high-CC) or a high score of emotional overinvolvement (high-EOI), the relapse risk was 0% in the patients living with a high-CC family not only in the SES+SFT group but also in SES group. In the patients living with a high-EOI family, the relapse risk was lower in the SES+SFT group than in the SES group (42.9% vs. 60.0%). These findings suggest that high-EE families should receive at least SES, and additional SFT should be given to families with specific needs.