The present investigation examined the effects of role stress and dispositional optimism on the well-being of 296 adult daughter caregivers who simultaneously occupied mother, wife, and employee roles. It was predicted that dispositional optimism would buffer the effects of stress in each of the four roles on psychological well-being (depressive symptoms and life satisfaction). Results provided some evidence to support the stress-buffering hypothesis. Dispositional optimism buffered (i.e., moderated) the effects of wife stress on depressive symptoms and life satisfaction. In addition, main effects of dispositional optimism on the psychological well-being were found, even after considering stressful experiences in particular social roles (e.g., caregiver). Findings suggest that dispositional optimism can serve as a beneficial resource that reduces the negative effects of wife stress on psychological well-being and contributes to adult daughter caregiver's well-being, irrespective of stress experienced in specific social roles, including caregiving.