Participation in leisure activities has been identified as a factor that favors inclusion in the community and it also contributes to a better quality of life. This study analyzed the influence of certain personal characteristics and environmental factors in the participation in leisure activities of youngsters and adults with developmental disabilities. A cross-sectional design was used with a convenience sample of 237 people, aged 17-65, living in the community. The participants completed the Spanish version of the Leisure Assessment Inventory, and information about the personal and disability-related factors was obtained through a questionnaire. Multiple regression analyses were conducted to determine the personal factors, disability-related factors, and perceived barriers to leisure participation. The results show that participation in leisure activities is determined more by personal factors and perceived barriers than by disability-related factors. (Contains 4 tables.)