This study examined the relationships between health literacy, self-efficacy and preventive care utilization among older adults in Taiwan. The data were from a longitudinal survey, "Taiwan Longitudinal Study in Aging" in 2003 and 2007. A total of 3479 participants who completed both two waves were included for analysis. Health literacy first was constructed through education, cognitive function and disease knowledge through structural equation modeling (SEM); then, the associations of health literacy to later self-efficacy and preventive care were examined. The model fit of SEM was good, indicating that the construct of health literacy was appropriate. Healthy literacy showed a moderate positive effect on self-efficacy and a small positive effect on preventive care utilization. Health literacy increases self-efficacy and utilization of preventive care. Promoting people's health knowledge and health literacy is suggested. © 2012 Japan Geriatrics Society.