AbstractAn Erratum has been published for this article in Infant and Child Development 10(4) 2001, 241.This paper compares the language development of pre‐school children born to teenage (n=22) and comparison mothers (n=20) and examines the extent to which differences in language development can be explained by social background, child and parenting factors. Mothers and children were assessed at home using a range of measures, including a structured interview, the language scales of the Child Development Inventory, the HOME Inventory, and videotaped mother‐child interaction. Results showed that children of teenage mothers perform significantly poorer than children of comparison mothers on measures of expressive language and language comprehension. Subsequent analyses showed that these differences are largely explained by differences in the parenting behaviour of teenage and comparison mothers. Specifically, maternal verbal stimulation and intrusiveness accounted for the relationship between teenage motherhood and children's poorer language comprehension, while maternal intrusiveness and involvement with the child account for the relationship between teenage motherhood and children's poorer expressive language development. These findings highlight the importance of early mother–child interaction for children's language development. Copyright © 2001 John Wiley & Sons, Ltd.