Objectives : This article aims to find how effective the art therapy is on the improvement of the self expression and the interpersonal relations with others, as medium for verbal communication of schizophrenic patients. Methods : The subject of this study was one schizophrenic patient who had been treated with drugs for five years in W university hospital, as well as counseled by an art therapy oo counsel office in J city. The art therapy had been performed the total 25 sessions, fifty minute per session, one session per week, from November 28 in 2008 to April 27 in 2009. The test was by HTP. Results : The results of this study are as follows: First, in the pretest of HTP, the subject showed a little lethargy, painting very simple house-shaped figures and too simple rectangular figures corresponding to those painted by 4 or 5-year-old children. In the post-test, however, the structures of houses were described concretely and three-dimensionally, and the descriptions of people were changed into concrete figure, by which we could see the improvement effect on the self expression and the interpersonal relations. Second, in the earlier stage, there was little verbal self expression, and little self respect, staring into space and showing passive attitude without positive assertion and expression. In the later stage, however, there were positive assertion and expression, even showing sense of humor. Lastly, in the earlier stage, there were few interpersonal relations. In the later stage, however, eye contacts and the interpersonal relations were increased during conversation and in the art work process, respectively. Conclusions : These results suggest that the art therapy can be effective on improvement of the self expression and the interpersonal relations with others, as medium for verbal communication of schizophrenic patients.