The purpose of this study was to determine the effect size of music therapy regarding family-related variable by meta-analysis where master/doctoral theses and journal articles were included. As a result, 143 effect sizes were derived from 31 studies. Overall mean effect size was 0.333, indicating a medium effect size. When it was analyzed by variable, regarding family characteristics, it showed a medium effect size in family with disease and disability. For other families, a medium effect size was observed. Regarding participated family member type, it showed a large effect size when mixed members participated in music therapy. Regarding intervention purpose, relationship between family members had the largest effect size. In case of program configuration type, music therapy which consists of songwriting, playing musical instrument, or others (music drama, etc.) showed a large effect size. In regards to total number of sessions and time per session, 9 to 15 sessions and 40-50 minutes showed the largest effect size, respectively. Finally, regarding researcher’s major, music therapy by music therapy major researchers was more effective than one by the other major researchers.