Problems related to social, emotional and psychological well-being in children at an early age may cause behavioural problems. Previous studies show that the development of emotion regulation strengthens social-emotional well-being, and psychological resilience and reduces behavioural problems in children. This study aims to test the possible mediating role of emotion regulation and to gain a better perspective on the association between social and emotional well-being, resilience, and behavioural problems. 250 children aged 4-6 years (122 boys, 48.8%; 128 girls, 51.2%; mean age = 4.93) studying in kindergartens in Turkey were included in the study. Data on children's behavioural problems and emotion regulation skills were obtained from mothers, and data on social-emotional well-being, and psychological resilience levels were obtained from teachers. Social and emotional well-being, and psychological resilience indirectly significantly predicted behavioural problems through  emotion regulation. Emotion regulation has a partial mediator role in the relationship between social and emotional well-being, psychological resilience and behavioural problems. In line with the results, the importance of supporting the development of emotion regulation skills in the preschool period was emphasized.