Abstarct: A mexta-analytic approach was adopted in this study to investigate the effectiveness of reader’s theatre (RT) on students’ reading fluency. To develop this empirical study, 18 primary RT studies from 2000 to 2018 were included. The study addressed two questions: What is the overall effectiveness of RT? What variables moderate the effectiveness of RT? Eight moderator variables including grade level, reading level, reading aloud, guided reading, feedback, explicit RT instruction, RT intervention period, and publication type were identified. In this review, evidence was found on positive and significant effects of RT on learners’ reading fluency (Hedges’ g=1.05); yet its efficacy was mediated by its various moderators. Findings contribute to a better understanding of using RT technique in EFL and ESL classrooms by addressing teachers, materials developers and policy makers. Future studies can relatively gain access to rich data concerning their research questions by adopting a mexta-analysis approach.