Massively Multiplayer Online Role-Playing Games (MMORPGs) are steadily gaining popularity as language learning tools among second and foreign language learners. The purpose of the current study is to explore the language learning findings of previous studies published from 2008 to 2018 through database searches using the keywords: ‘MMORPGs’, ‘online RPG’, ‘RPG’, ‘language learning’, and ‘English education’. Thirty articles that met the research requirements were selected. A qualitative content analysis was adopted to analyze previous studies, dividing them into three categories: 1) game design, 2) language skills and knowledge, and 3) pedagogical processes. Additionally, a theoretical framework was employed in the current study, classifying the content of previous studies into three categories: cognitive, social and affective perspectives, with each category linked with language learning theories including cognitivism, constructivism, socio-cultural perspectives, and behaviorism. The results indicated that the outcomes in MMORPG language learning could be classified into specific themes: communication, collaboration, interaction, and motivation. The design of MMORPGs (character, narrative environments, and quests) has an impact on learning experiences and engagement. The possibilities and potentialities of using MMORPGs were addressed in terms of mediating language learning between real and virtual worlds. Suggestions were made to implement the use of MMORPGs for future language learning in English education based on Csíkszentmihályi’s (2000) flow theory.