This study was conducted to explore the relationships between the elderly's existential identity and psychological well-being in accordance with the elderly's age-identity so as to improve the quality of life in the elderly with prolonged lives. The data were collected from respondents who were more than 60 years in age who live in city Suncheon. The statistics used for the data analysis were reliability, frequency, percentage, mean, standard deviation, one way analysis of variance, and multiple regression. The results of this study were as follows: (1) A majority of the elderly (49.8%) acknowledged psychological age as actual age. (2) The degrees of the elderly's existential identity was 54.90, while the degree of the elderly's psychological well-being was 33.07. (3) The elderly's existential identity level was significantly affected by economic state, spouse, age-identity, monthly living expenses, household, religion, career, age, and health state. Further, the elderly's psychological well-being level was significantly affected by existential identity, economic state, spouse, health state, age-identity, monthly living expenses, household, education, career, and age. (4) The variables that affect the elderly's existential identity were age-identity, economic state, health state, religion, monthly living expenses, and career, indicating an explanatory power of 38%. Moreover the variables that affect the elderly's psychological well-being were existential identity, age-identity, economic state, health state, and monthly living expenses, explaining approximately 55% of the total variance.