Graduate online learners have specific needs and challenges highlighted in the research on graduate online education. This systematic review examined 271 studies on broader research themes on graduate online education. Publication trends by year and journal outlets were analyzed. Descriptive statistics were tabulated for research context, participants, discipline, methods, and research themes. Among the studies published on graduate online education in this review, 59% were published in the United States, with 32% studied at the master's level and 59% in the education discipline. About 39% of the studies used quantitative methods, while 37% used qualitative methods. Online engagement was the most studied research theme (24%), followed by learner characteristics (13.7%) in graduate online education. Very few studies (5.2%) focused on the organizational level. Implications for online graduate learners, instructors, program directors, administrators, and future research recommendations are provided.