The purposes of this study were to clarify the characteristics of psychological changes in middle age from the viewpoints of eight stages of ego identity in Erikson's Epigenetic Scheme (1950), and to specify the reconfirmation process of ego identity and identity status. Method: a sentence completion test (SCT) was carried out by 49 subjects between 40 and 56 years old, and an interview was done to 22 of them. Results: (1) There were positive and negative aspects in the psychological changes in middle age.(2) The process of ego identity reconfirmation in middle age had the following four stages: a) The crisis period with the awareness of the changes of somatic sensation; b) The period of the psychological moratorium; c) The period of modification or turnabout of the life track; and d) The period of ego identity reconfirmed.(3) Four Identity Statuses were specified by the analysis from the viewpoint of Marcia (1964)'s identity status. These findings suggested that middle age was one of the transitional period in life cycle playing an important role for identity achievement.