Peer counseling' developed with increasing demands about human growth and prevention. It means various interpersonal supporting activities by laymen. It is for teaching laymen the supporting activities that enables to help peers. 'Gifted underachievers' means the learners whose academic achievement is under their potential ability. However, we can expect them to overcome this problem if there are some stimuli on their hidden ability by peers. In this sense, that is different from 'gifted learning disabled.' Through peer counseling, it is expected that they will have self-confidence about their own ability. Also they can cure their peers' problem. Peer counseling model in this paper is aimed to gifted underachievers as a kind of group counseling. This paper suggests a 5-step model : preparation → planning →training →activity →evaluation. More specifically it suggest peer counselor training such as 1) Basic education of peer counselor 2) Creating new self-image 3) facilitative communication skills training 4) problem-solving communication training 5) problem-solving training 6) motivation training 7) method and procedure of supporting activities.