It is known that the personality is the crucial factor in the treatment outcome of depression. The authors tried to identify the results of such studies and various components which determine the treatment outcome of depression. Nearly 60 papers published between the year 1990 and 2000 about the treatment of depression and personality were reviewed. Among them about 30 papers were selected to compare the research methods, results and discussions. The arguments and critics of the papers were discussed. In the many debates, the authors admitted the fact that premorbid personality trait influences the treatment outcome of depression negatively regardless of treatment method. Subtyping of depression is feasible along the presence of good or bad predictors of treatment outcome for depression. Differentiation of depression and personality seems to have no problem, however test of personality state before the development of psychiatric disorder such as depression is not amenable. For example, cluster A personality trait is often misunderstood as depression in clinical setting. In some cases cognitive behavioral therapy is effective in the treatment of depression accompanying personality disorder. The authors insist that the analysis of personality in the dimensional aspect rather than in the categorical aspect gives more information in the research of personality influencing the treatment outcome of depression. In addition, the reason why we understand the relationship between depression and personality were discussed.