The aging process causes the elderly to experience physical, psychological, and socio-cultural changes. These changes might affect the elderly in doing their daily activities, especially the instrumental activities of daily living (IADLs) and affect their mental state, particularly their psychological well-being. The objective of this research was to describe the instrumental activities of daily living (IADLs) and psychological well-being of the elderly in Banda Aceh. This quantitative-descriptive research was conducted by using a cross-sectional study design. A number of 210 respondents were chosen as the samples by means of a purposive sampling technique. The data were collected by distributing the questionnaires measuring the instrumental activity of daily living (IADL) by Lawton and psychological well-being by Ryff. The data were then analyzed by using a frequency distribution. The results show that by considering the IADLs, 154 respondents (73.3%) were in the independent category and 56 respondents (26.7%) were in dependent (needing assistance) category. In addition, the psychological well-being of 196 respondents (93.3%) was in high category while that of 7 respondents (3.3%) was in medium category, and that of the other 7 respondents (3.3%) was in low category. Hence, it is suggested that the elderly maintain their physical and psychological health in order to support the completion of their IADLs and improve their psychological well-being.