Abstarct: The purpose of this research was to investigate the effect of serious leisure time on the life satisfaction of disabled athletes with the mediating role of social support and happiness. The research method was applied in terms of purpose and descxriptive-survey in terms of data collection method. The statistical population of this research was the disabled athletes of Razavi Khorasan. Available sampling method was used to select the sample and 205 questionnaires were completed. Data collection tools were standard serious leisure time questionnaires (Gould et al., 2008), life satisfaction questionnaire by Diener et al. (1985), the Social Support Questionnaire by Zimmet et al. (1988), and the short form of the Happiness Questionnaire Oxford which was published by Hills and Argyle (2002). The formal and content validity of the questionnaires was confirmed by the opinion of 10 sports management professors. The construct validity of the questionnaires was also confirmed. In order to determine the reliability of the research tool, Cronbach's alpha and composite reliability were used. Data analysis was done by structural equation modeling method in PLS software. The results of the research data analysis showed that serious leisure time has a positive and significant effect on the life satisfaction of disabled people. Serious leisure time has a positive and significant effect on the social support of the disabled. However, social support does not have a significant effect on the life satisfaction of disabled people. Also, serious leisure time has a positive and meaningful effect on the happiness of disabled people. Happiness also has a positive and meaningful effect on the life satisfaction of disabled people. In addition, social support does not play a mediating role in the relationship between serious leisure time and life satisfaction of disabled people. Happiness plays a mediating role in the relationship between serious leisure time and life satisfaction of disabled people. Therefore, it can be concluded that participation in serious leisure activities can increase social support and happiness, and as a result, increase the life satisfaction of disabled athletes.