Creativity and innovation are essential agents for change processes and accelerating technical development. Having to face challenges, such as demographic change, organizations require individuals who are creative and innovative at each age. Previous research identified affect as a crucial determinant of creativity, even though empirical findings showed inconsistencies. Drawing on literature on age-related changes in affective experiences, we investigated the moderating effect of employees’ age on the association between daily positive and negative affect and creativity using a daily diary study. A total of 116 employees responded to daily questionnaires twice a day over five consecutive working days. As expected, hierarchical linear modeling analyses revealed differential effects regarding the affect-creativity association, dependent on employees’ age. Although older employees were most creative on days when they experienced a high level of positive affect (compared to their mean level of positive affect), younger employees were particularly creative when experiencing negative affect (compared to their mean level of negative affect). We discuss practical implications on how organizations could provide creativity-enhancing work environments for employees at each age.