This study investigates the factors influencing physicians' willingness to share professional knowledge on web medical forums, using social exchange theory and considering both extrinsic and intrinsic motivations. A research model was developed to explore motivations such as shared vision, reputation, altruism, and self-efficacy. Data collected from 164 physicians through a conventional sampling method revealed that shared vision is the most significant factor influencing knowledge-sharing attitudes, followed by self-efficacy, reputation, and altruism.