The purpose of this study was to longitudinally analyze how the baby boomer generation's integrated preparation for old age affects the change trajectory of life satisfaction. Data were collected from the 4th to 7th years of the National Old Age Security Panel Data and analyzed with the potential growth model analysis method. The research results were as follows. First, the life satisfaction of the baby boom generation, examined through the unconditional model, showed a non-linear trajectory of change, maintaining a slightly increasing pattern over time and then slightly decreasing. Second, the effects of economic preparation for old age, emotional and social preparation for old age, and physical preparation for old age, which were examined through the conditional model, on the change trajectory of life satisfaction showed different results. The baby boomer generation's economic preparation for old age did not affect changes in life satisfaction. On the other hand, the baby boom generation who prepares for old age emotionally and socially had high life satisfaction in their early years, and the high life satisfaction showed a trajectory of change that was maintained over time. The baby boom generation, who is physically preparing for old age, showed a trajectory of change in which life satisfaction increased rapidly as time passed, although life satisfaction at the beginning was insignificant. Based on the results, a proposal was made to promote volunteer activities and lifelong education, expand social networks, and policies and services related to health promotion and disease prevention.