This integrative review examined 38 published articles on the topic of formative assessment conducted in South Korean EFL settings, from 2014 to 2023. Despite strong interests in using quality formative assessments that are aimed at improving English learners’ performance, no prior systematic analyses have been performed to date. To that end, this study draws on Wiliam and Thompson’s (2008) conception of the formative assessment five-strategy model, and Yan and Pastore’s (2022) Teacher Formative Assessment Practice Scale (TFAPS), as a guiding framework to examine the extent to which formative assessment research conducted in South Korean EFL classroom settings has enacted the five key strategies and thereby promoted learning and improved teaching. For all five key strategies, more studies showcased weak evidence of implementing each strategy, and that positive student learning was more likely to be seen in studies that fully, or nearly fully, implemented the key strategies. Recommendations for enhancing formative assessment teaching and research practice are provided at the end.