Research has shown links between emotion regulation strategies and child mental health. However, it is not well known how the characteristics of children may moderate these links. The aim of this study was to explore whether environmental sensitivity--the ability to perceive and process information about the environment--moderates links between emotion regulation strategies (cognitive reappraisal and expressive suppression) and children's emotional and behavioral problems. The study included 1381 children (M[subscript age] = 10.53, 51% girls) who gave information about their emotion regulation and environmental sensitivity, and whose teachers reported on their emotional and behavioral problems. The results showed that suppression predicted a higher amount of problems for girls regardless of their sensitivity level. For boys, environmental sensitivity moderated this link. Among more environmentally sensitive boys, the association between suppression usage and emotional and behavioral problems was stronger than among less sensitive boys. These results show that the effects of suppression may be exacerbated depending on the child's gender and environmental sensitivity.