This study examined differences in emotion regulation strategies and happiness among three age groups: young (18 - 35 years), middle-aged (36 – 62 years), and older adults (63 years and older). Also, emotion regulation strategies (reappraisal and suppression) were examined as a mediator in the relationship between age and the level of happiness in individual. Results show that young and older ... [Show full abstract] adults differ in their use of suppression and the level of happiness. Middle-aged adults did not differ in their use of suppression and the level of happiness, when compared to young and older adults. Analysis of gender differences revealed that men used suppression more often than women. There were no gender differences in use of reappraisal among participants. Suppression was found to be a mediator in the relationship between age and happiness. Further, suppression is related to age and level of happiness in individual negatively. In contrast, reappraisal has no impact in a relationship between age and happiness and it was not related to the level of happiness in individual. In conclusion, results suggest that use of suppression differ among the age groups and suppression mediates the relationship between age and the level of happiness in individual.