Today's dynamic distance learning environments offer a flexible, comfortable, and lifelong learning experience, independent of space and time. In this way, it also supports and develops existing traditional training programs. The increasing importance of knowledge, skills and learning in today's technological life cycle has led to an increase and diversification of research and applications in distance learning. Accordingly, distance learning literature has a rich content supported by a multidisciplinary background. From this point of view, it is crucial to perceive the research landscape reflecting the general themes and trends studied in the field of distance learning. This study aims at revealing the distance learning research themes and trends by analyzing the 27,735 articles of journal conducted in the last decade. The methodology of the study is based on semantic content analysis implemented by N-gram-based text categorization technique. As a result, 10 main themes are discovered, namely, "System establishment", "Media", "Assessment", "Method", "Content", "Education levels", "Learner", "Research methods", "Interaction-Communication", and "Resource-Material-Tool". In this context, the findings of the study are expected to provide significant insights to guide prospective research and practice in the field and to develop continuous improvements and standards for distance education communities.