The purpose of this study was to prospect the direction and tasks of gratitude research through the review of the psychological experiment researches in gratitude. The definition, psychological traits, and scales of gratitude were surveyed. And the effects of gratitude on happiness and mental health was examined. The possibility of development and efficacy of gratitude enhancing program was reviewed. As a result, the followings were discussed. First, the psychological researches defined the gratitude as affect. But the definitions including cognitive and behavioral aspects should be considered and the scales should be developed. Second, the development process, time, possibility and aspects of change in gratitude disposition should be investigated from the multidimensional approaches. Third, the subject should be extended to the children, the adolescents, and the aged. And the effects of gratitude disposition on the task accomplishment and the academic achievement should be examined. Fourth, the systematic programs included cognitive, behavioral, and motive elements should be developed and applied. Finally, the cultural and the individual differences of experience level, intensity and expression aspects in gratitude should be checked.