Learning involves interactions among three factors; content, instructor and the learner. As the constructivism was introduced and applied to education, interactions among these three factors have become more active and multidirectional such as content-learner, instructor-learner, and learner-learner. In addition, the union of computer network with the constructivism makes it possible to increase the opportunity to contact anyone at any place at anytime and to improve the quality of communication by filling the gap between those who have more information and the have-not\'s as well. Comparing with the traditional classroom, the learning environment and the learning process of web-based instruction has been remarkably changed. Instructors should be equipped with new roles and competencies so they can effectively cope with the new learning situation. The questionnaire survey was conducted to 12 Korean on-line facilitator who are currently facilitating web-based courses on a virtual campus. The result is that Korean online facilitators are well performing the pedagogical, managerial and technical roles and have the appropriate competencies. But they do not still perceive nor fully perform the online social roles. This research provides five suggestions to enhance online social roles ; First, instructional frames should be designed to activate interactions among participants. Learners should get the concept that online social activities are not options but learning activities. Second, in the beginning of a course, providing a sort of online events for formal or informal social interactions may be helpful. This makes participants easily get accustomed to the online social communication. Third, orientation for new facilitators is essential. Letting them perceive their new roles is important. Forth, the number of learners per online class should be limited so that one facilitator can manage the interactions among the whole participants. Fifth, individual characteristics and personality is the key to the selection of online facilitator. One who really enjoys helping others will be the best facilitator.