Although emerging evidence suggests that parental behavior is related to the development of child executive functioning (EF), the mechanisms through which parenting affects child EF have yet to be investigated. The goal of this study was to examine the potential mediating role of child language in the prospective relation between maternal autonomy support and child EF. A total of 53 mother-infant dyads took part in three home visits at 15 months, 2 years, and 3 years, allowing for the assessment of maternal autonomy support (T1), child expressive vocabulary (T2), and child EF (T3). The results suggested that child language played a mediating role in the relation between maternal autonomy support and child performance on EF tasks entailing a strong impulse control component above and beyond child previous EF and family socioeconomic status (SES). In contrast, no such mediating role of language was found with EF tasks tapping mostly into working memory and set shifting. Thus, this study highlights one pathway through which parenting can affect child executive control. (Contains 2 figures and 4 tables.)