Although personal resources of caregivers, such as coping skills and social support, have been shown to be important in understanding caregiver stress and health outcomes, personality traits have not previously been considered. The purpose of this study was to examine the association between the personality traits of neuroticism and dispositional optimism and mental and physical health outcomes. It was predicted that personality would have direct effects, and indirect effects through perceived stress, on health outcomes. Participants were spouse caregivers of patients diagnosed with Alzheimer's disease. Results showed that neuroticism and optimism were significantly related to mental and physical health. Furthermore, neuroticism had significant direct effects on all of the health outcomes, and substantial indirect effects, through perceived stress, on mental health outcomes. Optimism showed stronger indirect than direct effects on all health outcomes. These findings demonstrate the importance of including personality of the caregiver in theoretical and empirical models of the caregiving process.