The purpose of this study was to analyze the factors influencing life satisfaction in widowhood among older females. Using the sixth Korean Retirement and Income Study (KReIS) supplementary survey data, a total sample of 1,471 women aged 65 or older whose spouse had died were selected, divided into 508 young-old (65–74), 745 middle-old (75-84), and 218 oldest-old (85+). Then, factors influencing the life satisfaction of these three groups were analyzed, based on a combination of perceived health and interpersonal satisfaction levels. It was found that among the young-old group, a higher level of subjective health perception indicated by monthly income and material support and interpersonal satisfaction linked to more frequent participation in community gathering combined for an overall higher level of life satisfaction. For the middle-old group, higher life satisfaction was provided by monthly income, informational support, and material support for subjective health perception and no diseases for interpersonal satisfaction. The oldest-old group with higher life satisfaction referred to monthly income for subjective health perception and no experience in donation activities for interpersonal satisfaction. Based on these findings, this study provides implications for policy and practice to improve the life satisfaction of elderly women who have experienced their spouse’s death.