Experiencing chronic stress early in life has been linked to anxiety symptoms and related outcomes. This study examined whether emotional self-regulatory processes, specifically children's awareness of emotion regulation strategies, would qualify the link between cumulative stress and anxiety symptoms in childhood. One hundred and twenty-nine 6- to 11-year-olds (M = 8.84; SD = 1.61; 47% girls) participated in the study. We derived an index of nine environmental stressors and quantified children's emotion regulation strategy awareness from an interview about their emotional experiences. Parents reported on children's anxiety symptoms. As expected, cumulative stress was positively associated with anxiety symptoms. Emotion regulation strategies moderated the effect of cumulative stress on anxiety symptoms, such that children with larger repertoires had fewer symptoms in the context of low stress, but more symptoms in the context of high stress. Results offer new insight in understanding anxiety symptoms in childhood and demonstrate the importance of children's emotion regulation strategy knowledge as a novel facet of regulatory skill that may characterize the specific emotion dysregulation implicated in the emergence of psychopathology.