We examined the relations between language skills and behavior problems and whether social skills mediated these relations among preschool children enrolled in Head Start programs. Participants included 242 preschool children and their parents in Head Start programs. Over a 2-year period, parents and teachers reported children’s behavior problems using the Child Behavior Checklist Ages 1½-5, and social skills using the Social Skills Improvement System-Rating Scales. Children’s expressive and receptive language skills were assessed individually using the Preschool Language Scale-5. Results suggested that children’s early receptive language predicted later teacher-reported child internalizing and externalizing behaviors. Social skills did not mediate associations between language skills and parent- or teacher-reported child behavior problems. (author abstract)