Tawesak Tanwandee, MD, FAASLD, AGAF, is a hepatologist in the Division of Gastroenterology and Hepatology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand, where he has served for the past 35 years. He currently holds the position of Professor of Gastroenterology.

He received his medical degree with First Class Honours and a Gold Medal, and is board-certified in Internal Medicine and Gastroenterology by the Medical Council of Thailand. He subsequently spent two years as a research fellow in the Department of Molecular Virology, Baylor College of Medicine, Houston, Texas.

Professor Tanwandee is President-Elect of the Thai Association of Gastroenterology (2025–2026), a Steering Committee member and Past President of the Asian Pacific Association for the Study of the Liver (APASL), and Past President of the Thai Association for the Study of the Liver (THASL). He is a member of the AGA, ACG, AASLD, EASL and APASL.

His research interests focus on the treatment of chronic hepatitis B and C, hepatocellular carcinoma, and the cost-effectiveness of hepatitis B and C therapy.