Online discussion is a major form of discourse in modern society and a teaching-learning method that is important in an online learning environment. The purpose of this study is to explore the research direction by considering the research on online discussion. The subjects of the analysis are the title, keywords, and abstracts of Academic papers from 2011 to 2020. After conducting textual analysis, conduct LDA-based topic modeling with Gibbs sampling and conduct time series analysis for analysis of research trends over the years. Seven topics were extracted through topic modeling. These are classified into two aspects, respectively: online discussion as teaching-learning methods and online discussion as online discourse forming methods. Among them, research on aspects of online discussion as teachinglearning methods in online class settings has been addressed as a relatively more important topic. According to the annual time series analysis, the research topic on online discussion as teaching-learning activity decreased, but after COVID-19, remote classes began to be introduced in earnest, and it began to increase rapidly again. On the one hand, research related to dashboard and visualization analysis for learner interaction analysis has shown a steady increase. Topics on online discussion as an act of social participation or political communication have emerged as a cold topic, while topics on discourse analysis in online communities of members of society based on online discussion have emerged as a hot topic. Based on these findings, We discussed the direction of follow-up research for the continuous and significant development of online discussion.