The purpose of this study was to identify the key success factors of medical tourism using the case of South Korea. Medical tourism refers to the phenomenon of travelling across national borders intentionally to access a variety of medical treatments, especially modern medical treatment. Through conducting semi-structure face-to-face in-depth interviews with the service suppliers of Korean medical tourism, it was discovered that Korean medical tourism has been facilitated by the effect of Hallyu and advanced Korean brand power. More importantly, tourism activities for companions and extra support for patients’ convenience are identified as important success factors of Korean medical tourism, suggesting that the medical tourism industry not only includes medical services but also involves tourism perspectives, supporting the patient and their companions to stay in a comfortable and pleasurable environment. This study generated results which are valuable for both academic and industry perspectives, as this is a field which has not been extensively researched. Medical tourism representatives in other countries can consult these findings to develop the industry.