Kindergarten readiness is shaped by both family and school contexts, highlighting the importance of an ecological perspective on early learning. The current study examined whether parental engagement mediates the relationship between parents' protective factors (e.g., social support) and children's kindergarten readiness when controlling for parental education. Participants included 853 kindergarten students whose readiness was assessed using the Kindergarten Student Entrance Profile (KSEP). A mediation analysis using Hayes' PROCESS macro revealed that parents' protective factors were indirectly associated with kindergarten readiness. Protective factors predicted higher parental engagement, which in turn predicted higher readiness scores. These findings underscore parental engagement as a key pathway through which protective factors support children's early learning. Implications for school psychologists and educators include strengthening family-school partnerships and providing resources that promote both caregiver engagement and involvement in children's learning to foster equitable kindergarten readiness.