Objective: This study was aimed to analyze the effects of activities using picture books for young children’s language development and to identify factors that caused differences in these effects by applying meta-analysis. Methods: We conducted a homogeneity test of effect sizes on 21 Korean studies published in academic journals from 1990 to February 2018 and calculated the effect size by applying a random effect model. Additionally, we conducted a meta-ANOVA to investigate whether the effect sizes differed by types of language development, picture book activities, and environmental variables-such as place, time, and agent. Results: The results indicated that the effect sizes of the 21 studies were heterogeneous and the total effect size was 0.90, which was significantly large according to Cohen s standard. The effect sizes also varied by types of language development, picture book activities, and environmental variables. Conclusion/Implications: To increase the effects of activities using picture books for young children’s language development, this study suggested the importance of picture book activities to be integrated with other play areas, teaching methods, and other print materials for the development of literacy abilities, and the link between home and early childhood education institutions.