This study aimed to examine the longitudinal independent associations of objectively assessed physical activity at different intensities, including moderate-to-vigorous physical activity, light physical activity, and sedentary behaviors, with dimensions of subjective well-being in older adults. A total of 307 community-dwelling older adults aged 65 or older in Taiwan were interviewed in 2012. Physical activity was assessed using triaxial accelerometry. Subjective well-being was measured using the Chinese Aging Well Profile. Among them, 295 attended an 18-month follow-up study in 2013. Hierarchical linear regression models with adjustment for socio-demographic variables, lifestyle behaviors, health status, accelerometer wear time, and state of well-being at baseline were performed. The hierarchical regression models (step one) demonstrated that moderate-to-vigorous physical activity was associated with higher levels of follow-up general and specific dimensions of well-being (β=0.19-0.24) with the exception of material and environmental well-being. After light physical activity was further included in the models (step two), the associations of moderate-to-vigorous physical activity with general, physical, and independence well-being remained, while the contribution of light physical activity was not significant. In contrast, light physical activity was a significant predictor of psychological, learning and growth, and social well-being in these models (β=0.20-0.24), while these associations with moderate-to-vigorous physical activity were attenuated or not significant. Sedentary time was not related to any dimension of well-being. The findings indicate that moderate-to-vigorous physical activity and light physical activity are associated with different dimensions of well-being, suggesting that different intensities of late-life physical activity make distinct contributions to well-being.