Limited time, physical and financial opportunities in education has caused the expansion of the education system and emergence of new alternatives. One of these alternatives is open education that emphasizes the philosophy of sharing the information and materials used in learning and teaching freely and openly, and one is distance education that offers a formal form of education blended with information systems and the internet. Anadolu University Open Education System, not only in Turkey, in many countries around the world offers learners the opportunity to open and distance learning. In this sense, it has one of the largest student communities in the world. Therefore, evaluating the efficiency of a large and powerful organization like the Anadolu University Open Education System has gained importance. This study was carried out to determine the activities of associate degree programs in Anadolu University Open Education System in the fall and spring semesters of 2016-2017, 2017-2018, 2018-2019 academic years. Anadolu University Open Education System associate degree programs are ranked according to their effeciency values, by the Slack-Based Measure Analysis.