Online education has been growing in demand over the years across universities and colleges. However, online learners frequently experience social isolation, which negatively impacts their learning experience and outcome. In this chapter, we investigate the design of AI-based social matching systems to help foster social connections among online learners in higher education context. Specifically, we seek to answer three core design questions: (1) What data should be collected to facilitate students’ social interaction process? (2) How to design technology to support students’ interactions with one another? (3) What are students’ concerns about the use of AI-based social matching systems? We begin by exploring the feasibility, design, and concerns of AI-based social matching through existing literature. We then present our ongoing work on the design and use of AI conversational agents as social matching systems in the online learning context. Finally, we outline future directions for research on designing human-centered social matching systems in online learning.