The objective of this study is to develop a mother's reactions to early adolescents' anger. To supplement and reconstruct existing scale, original scale was translated and re-translated. Then after conducting free-response questionnaires with a sample of 100 students, the questions regarding a mother's reactions to early adolescents' anger were added and revised. In this part of the process, 41 questions were selected after the content was validated by 2 Doctorates of Youth Studies. With this existing scale, we investigated 620 middle school students in 2 different cities. The data were analyzed by SPSS (ver.25) and Amos (ver.25). Major statistics used to analyze the data were reliability analysis, exploratory factor analysis, confirmatory factor analysis, Pearson’s correlation analysis. Major results are as follows. First of all, for validation of item quality, we conducted a correlation analysis between items, average, and standard deviation analysis, and squared multiple correlation (smc) analysis, and the result was satisfactory exept for one item. Second, for construct validity using exploratory factor analysis, 33 items were categorized into 4 factors: anger-dismissive reactions, anger-supportive reactions, anger-neglect reactions and anger-override reactions. To secure the stability of factor structure, the confirmatory factor analysis, and convergent-discriminant evidence were certified to be reliable. In third, for criterion-related validity, sub-factors of the scale had a meaningful correlation with the variables of adolescents. These results imply that the scale of mother's reactions to early adolescents' anger was varified.