Introduction Health-promoting lifestyle can leads to improving the quality of life, life satisfaction, well-being and reducing the burden of health care in the society. This study was carried out to investigate the mediating role of health-promoting lifestyle and moderating role of ethnicity in the effect of cultural capital and subjective socioeconomic status on life satisfaction in Iran. Methods This cross-sectional study was conducted with 800 respondents in the cities of Kermanshah with Kurdish ethnicity and Tabriz with Azeri ethnicity. The data gathering tool was a questionnaire in five section including demographic checklist, cultural capital questionnaire (2015),Diener’s life satisfaction scale, and health-promoting lifestyle questionnaire (HPLP II), and socioeconomic status scale. Data were analyzed by SPSS and AMOS software. Results Life satisfaction had the highest correlation with the objective dimension of cultural capital (p < 0.001 r = 0.298). The direct standardized coefficient of the path of cultural capital to health-promoting lifestyle was 0.44 (P < 0.001). Also the direct standardized coefficient of cultural capital on Life satisfaction was 0.04 that was not significant. The standard coefficient of the path of cultural capital on life satisfaction through health-promoting lifestyle was 0.27(P < 0.001). Ethnicity variable did not moderate the effect of cultural capital on life satisfaction (p > 0.05). Conclusion The results of this study showed that paying attention to the concept of health-promoting lifestyle is a necessity to affect life satisfaction. It can play a role as a mediator for the path of cultural capital and socio-economic status on life satisfaction. This study also showed the role of ethnicity as a moderating variable in the relationship between socio-economic status and health-promoting lifestyle.
