In order to lead a healthy and happy life for their remaining years, older people want to be healed up the past hurts they had ever experienced. One way to be healed up should be to forgive the persons who gave the hurts to the older people. Forgiving process is very much related to cognitive change, and factors of the cognitive changes in the forgiving process in old age are ➀ children’s ascent in their SES level, ➁ interaction with the others, ➂ deterioration in health, ➃ observation of death owing to a natural disaster, ➄ retrospection and healing of life through a religion, and ➅ indirect intervention such as educational programs. This study was to explore if there would be any differences in the cognitive change factors according to the time or age when older people had forgiven the persons. Participants were 80 men and 85 women who were aged from 60 to 83 years, and they were all who had ever experienced the serious emotional hurts in the past as well as had ever forgiven the persons who gave them the hurts. None of them have ever had any professional help on their hurts. They were asked when they had forgiven the past hurts, and asked to assess how much each cognitive change factor affected for their forgiveness acts on a 5-point scale, 0 (not at all) to 4 (very much). Data were collected thru a one-to-one interview. Data concerning the influence of each factor over the forgiveness were tabulated according to gender as well as the time when older people had forgiven the hurts. The major findings were that there were differences in cognitive change factors according to the time when older people had forgiven. For instance, interaction with the others was the most influential factor when the time of older people’s having forgiven was in their 30s or 40s, whereas children’s ascent in their SES level was in their 60s.