We explored the relationship between neighbourhood and social participation among older adults using a Living Environments and Active Aging Framework. This prospective cohort study used baseline data from the Canadian Longitudinal Study on Aging (CLSA) with a 3-year follow-up. Three aspects of social participation were the outcomes; walkability and greenness at baseline were exposure variables. The sample consisted of 50.0% females (n=16,735, age 72.9± 5.6 years). In males, higher greenness was associated with lower loneliness and less variety in social activities. No significant associations between greenness and social participation were found in females. High walkability was related to a higher variety of social activity and higher loneliness in males but not females, and less desire for more social activity in both sexes. Greenness and walkability impact social participation among older adults. Future research should include sex and gender-based analyses.