Background: Older adults often experience an increase in low-grade chronic inflammation. Purpose in life could act as a protective factor as it is associated with beneficial health outcomes. Purpose in life may exert part of its adaptive function by promoting persistence in goal pursuit. During older adulthood, however, when many individuals experience an increase in intractable stressors and declining resources, the adaptive function of purpose could become reduced. Purpose: We examined whether the association between inter- and intra-individual differences in purpose in life and chronic inflammation differed across older adulthood. Method: We assessed four waves of data among 129 older adults (63-91 years old) across 6 years. Results: Hierarchical linear modeling demonstrated that within-person increases in purpose in life predicted reduced levels of chronic inflammation in early old age (25th percentile or 73 years, coefficient = -.016, p < .01), but not in advanced old age (75th percentile or 81 years, coefficient = .002, p = .67). Between-person differences in purpose were not related to chronic inflammation. Conclusions: These results suggest that greater within-person increases in purpose may protect health processes particularly in early old age but become less effective in advanced old age.