Objectives: School-aged children with poor reading abilities face a variety of challenges in their lives. They may be at risk of having learning difficulties and behavioral or emotional problems in school. The purpose of this study is to analyze the relationships among reading abilities, pragmatic language abilities, and socio-emotional behaviors and the mediation effect of pragmatic language abilities in the relations between reading abilities and socio-emotional behaviors of school-aged children. Methods: The participants in this study are 124 elementary school children (from 2nd to 6th grade). To examine the relationships among reading abilities, pragmatic language abilities, and socio-emotional behaviors, correlations were used. To analyze the mediation effect of pragmatic language abilities in the relations between reading abilities and socio-emotional behaviors, SPSS PROCESS Macro (ver. 3.5) analysis method was used in Model 4. Results: The main findings of this study are as follows. First, reading abilities were significantly correlated with pragmatic language abilities and socio-emotional behaviors. Also, the pragmatic language abilities were significantly correlated with socio-emotional behaviors. Second, pragmatic language abilities mediated the relations between reading abilities and socio-emotional behaviors (emotional difficulties and strengths). Conclusion: The significance of this study lies in verifying that reading abilities and pragmatic language abilities play an important role in alleviating socio-emotional problems and in increasing emotional strengths. These results can be used as important basic data for reading and practical language intervention to reduce emotional difficulties and to increase emotional strengths.