Accumulating evidence shows that a higher sense of purpose in life is associated with lower risk of chronic conditions and premature mortality. Health behaviors might partially explain these findings, however, the prospective association between sense of purpose and health behaviors is understudied. We tested whether a higher sense of purpose at baseline was associated with lower likelihood of developing unhealthy behaviors over time. Prospective data were from the Health and Retirement Study, a national sample of U.S. older adults. Our sample included 13,770 adults assessed up to five times across eight years. Among people who met recommended guidelines for a given health behavior outcome at baseline, those in the top versus lowest quartile of purpose in life had 24% lower likelihood of becoming physically inactive (95% CI: 0.68–0.85), 33% lower likelihood of developing sleep problems (95% CI: 0.58–0.79), and 22% lower likelihood of developing unhealthy body mass index (BMI) (95% CI: 0.69–0.87) in sociodemographic-adjusted models. Further there was a marginal reduction in smoking relapse (HR = 0.65, 95% CI: 0.41–1.03) and no association with heavy alcohol use (HR = 1.02, 95% CI: 0.81–1.29). Findings for physical inactivity, sleep problems, and unhealthy BMI remained evident after further adjusting for baseline health status and depression. Our results, suggest that a sense of purpose in life might emerge (with further research) as a valuable target to consider for interventions aimed at helping older adults maintain some health behaviors. •Pathways underlying the purpose-physical health association remain unclear.•We evaluated associations between purpose in life and several health behaviors.•We tested this hypothesis in a large and prospective cohort of adults aged >50.•Higher purpose was associated with lower risk of becoming physically inactive.•And also lower risk of developing sleep problems and unhealthy BMI