Parents influence the development of children’s social understanding by using mental state terms that denote concepts which children are about to develop (Taumoepeau & Ruffman, 2006, 2008) or via the usage of contrastive and/or causal mental state talk (Peterson & Slaughter, 2003). The present longitudinal study examined parent-child dyads and assessed parental mental state talk (MST) during picture-book narration. Seventy-four parents told their children a story twice, when the children were 2 and 4 years old. The same wordless picture book was used to elicit the narration at each time point. Two criteria were used to classify MST: type of utterance (affective, perceptual, or cognitive) and complexity of utterance (simple or clarifying). Parental MST was more frequent in narrations to 4-yearolds than to 2-year-olds. Parents directed more complex MST to 4-year-old children than to 2-year-olds. Affective references were most common at both time points, while cognitive utterances hardly occurred. Nevertheless, growing trends were observed in all types of MST. The results suggest that parents match their MST to the children’s level of social understanding development.