International trade has become more complicated and is now related to more aspects of health and the health system. As Thailand is active in international trade and health, understanding what knowledge exists and determining the knowledge gap is essential for generating the necessary evidence in order to promote better understanding and allow evidence-based policy decisions to be made. This study reviewed the existence of knowledge on international trade and health issues in a scoping review, focusing on Thailand during the period 1991–2020. In total, 156 studies from seven databases and manual searching were included. Of these, 46% were related to trade in health services and 39% were linked to intellectual property, particularly access to medicines. This review found only a very small amount of research on other issues and did not identify any study on trade policies or products related to health and international trade and the environment. We therefore recommend that further studies should be carried out to provide more critical evidence—in particular, more research focusing on the impacts of trade on health-related goods and the analysis of the positive and negative impacts of international trade on industry is needed. Furthermore, better knowledge management through the publication of research findings and making them searchable on international databases will increase the visibility of international trade, increase our knowledge of health issues, and provide supporting evidence.