Introduction: Medical tourism is a recent form of travel that involves rapidly increasing overseas trips to address a variety of health issues. Medical tourism websites play a vital role in offering information and resources for people looking for medical treatment overseas. A well-designed and easy-to-use website can help build trust and credibility with potential patients. The aim of this study is to assess the usability of the leading medical tourism websites in Iran.Material and Methods: The present study was a descriptive and cross-sectional study. In this study, the usability of five top medical tourism website in Iran were evaluated using heuristic evaluation method. The checklist was based on Nielsen’s heuristics. The criteria for selecting the top websites were Alexa Rank Checker.Results: The median of usability problems rates in website1, website2, website3, website4, and website5 were 11.1%, 7.7%, 9.9%, 10% and 9.1%, respectively. The median severity of identified problems for website1, website2, website3, website4, and website5 were 2.6%, 2.9%, 2.9%, 2.9% and 2.8%, respectively. The principles of “help and documentation”, “visibility of site status”, and “Security and privacy” in the five websites were categorized into the “highest rate of problems”, “lowest rate of problems”, and “highest severity of problems” groups, respectively.Conclusion: By addressing usability issues of medical tourism websites, organizations can better serve their users and ultimately contribute to the growth of the medical tourism industry.