This article used the Rational Emotive Behavior Therapy of Ellis to provide assistance for a case with major depression in hospital. The treatment was aimed at helping the client to differentiate rational and irrational belief, so that she could reject irrational beliefs and produce new, rational beliefs, emotions and behavior. First we used a holistic nursing assessment to define the problem. The major health problems included a potential for hazardous suicidal behavior, sleep disturbance, and invalid coping. We helped the patient to controvert irrational beliefs in cognition by conducting eight individual interviews and helped her to recognize irrational beliefs by training with homework. We also found that the client's capacity for cognitive change was greater than those for changes in movement and in self-assessment. In addition, we found that REBT could improve the client's quality of sleep, disconsolate emotion and invalid coping. The client exhibited no suicidal behavior in hospital. In post-discharge follow-up, we established that the client's emotion was stable, and that she could handle housework, and continue to differentiate irrational and rational beliefs by using her own self-belief.