Objective Numerous studies on the effects of seclusion and/or restraint in acute psychiatric treatment have reported both positive and negative effects. However, no studies to date have evaluated the effects of seclusion and/or restraint on schizophrenia patients using a rating scale. Thus, to examine the effects of seclusion and/or restraint on schizophrenia patients, we used the Brief Psychiatric Rating Scale and assessed the psychological condition of patients. Methods Factor analysis was conducted to create subscales of Brief Psychiatric Rating Scale, and psychiatric changes were assessed with respect to each subscale using multiple logistic regression analyses. Analyses were performed on three groups (i.e. entire, higher functioning, and lower functioning groups) involving a total of 1559 schizophrenia patients aged 18 to 65 years. Results In the entire and lower functioning groups, seclusion was a significant predictor of improvements related to the "hostility/suspiciousness" subscale. Seclusion combined with restraint was associated with improvements related to the "psychosis/thinking disorder" subscale. In the higher functioning group, there were no significant predictors. Conclusions It is implied that seclusion and/or restraint is related to improved psychiatric symptoms only among patients whose functioning is impaired. To verify the present findings, further studies involving multiple sites and additional psychiatric measures are necessary.