Abstract: This study examines the topic of motivating social support provision for patients with complex chronic diseases (CCD) from a technological- affordance approach. Utilizing an online survey (N = 281) of patients with Irritable Bowel Syndrome (IBS), this study shows that certain technological affordances of computer-mediated technologies could trigger psychological reactions, which then drive social support provision for IBS patients in online health communities. Community building significantly promotes support provision by enhancing one’s sense of community, and so does agency building via improving one’s self-agency. In addition, browsing significantly promotes social support provision as individuals are more likely to be exposed to emotional support-seeking messages when technology allows users to freely move through and obtain information. As a result, they are more inclined to offer support in response. Theoretical and practical implications are discussed.