The aim of the study is to explore the role of child’s executive functions in the relation between child’s externalizing and internalizing problems and caregiver strain in early school age children. The caregiver strain refers to providing nurture and care for a dependent family member. A sample includes 175 caregiver-child dyads and 36 school teachers. Participants completed the Family Strain Index which measures caregiver strain or burden (caregivers), the Strengths and Difficulties Questionnaire which measures child’s externalizing and internalizing problems (teachers), and behavioral tasks that measure executive functions (children). Using structural equation modelling, the analysis resulted in a full mediation of the child’s externalizing problems on the caregiver strain by child’s executive functions. However, the association of child’s internalizing problems with caregiver strain has not been confirmed. These results indicate that better child’s executive functions buffer the negative effect of child’s externalizing problems on caregiver perceived burden. Based on these results, we can suggest that interventions should be focused on programmes to improve the child’s executive functions in the family and educational context, along with caregiver training aimed at providing emotional and social support, or individual therapy.