The present study examined the cultural differences and similarities in the levels and predictors of subjective well-being in Japanese and American centenarians. We analyzed data on cognitively intact Japanese (N = 59) and American (N = 125) participants from the Tokyo and Georgia Centenarian Studies, respectively. The Philadelphia Geriatric Center Morale Scale was used to measure subjective well-being, while sociodemographic, social, and health resources were assessed as potential predictors. The American participants reported higher scores on well-being (satisfaction with social relations and psychological comfort). However, cultural differences in the levels of well-being disappeared after we controlled for its predictors. The regression models revealed that health resources (cognitive function, hearing problems, and activities of daily living) were strong predictors of well-being in both countries. Social resources (living with others) were strongly associated with one dimension of well-being (attitude toward one's aging) among the Japanese participants. The findings support the existing lifespan and cross-cultural literature, indicating that declines in health impose certain limitations on adaptive capacity in oldest-old age irrespective of cultures, and that social embeddedness is valued in Eastern cultures. The authors speculate that cultural values, i.e. personal autonomy versus relational harmony, play an important role for well-being in oldest-old age.