Interventions that train parents to share picture books with children are seen as a strategy for supporting child language development. We conducted meta‐analyses using robust variance estimation modeling on results from 19 RCTs (Ntotal = 2,594; Mchildage = 1–6 years). Overall, book‐sharing interventions had a small sized effect on both expressive language (d = 0.41) and receptive language (d = 0.26). They had a large effect on caregiver book‐sharing competence (d = 1.01). The impact of the intervention on child language was moderated by intervention dosage, with lower dosage associated with a minimal impact. Child age and caregiver education level were unrelated to child outcome. This review and meta‐analysis confirms the promise of book‐sharing interventions for enhancing and accelerating child language development.