The purpose of the study was to know the effects of person-centered art therapy in reducing problem behaviors for a child who has ADHD symptoms. The subject of this study was a second grade elementary school boy whose mother requested art therapy. He did not complete his school works and could not concentrate on study while at school. He did not do his work by himself, did not his belongings clean, looked stunned and was distracted at home. The results of psychological tests (CAT, KFD, BGT, K-ARS), demonstrated that he was anxious and lethargic internally, and he was inattentive, hyperactive, and impulsive externally. To reduce these problems, he underwent person-centered art therapy, which lasted from August, 2009 to February, 2010. He attended the therapy once a week for 26 sessions. The results of this study show that there was no change in attention deficit, but hyperactivity and impulsivity were reduced. Moreover anxiety and lethargy were changed positively, and psychological energy was increased. Because this study is not generalizable, future research using various methods are needed.