John Weis, MD, is a Huntsman Cancer Institute physician and a clinical assistant professor in the Division of Oncology, Department of Internal Medicine, at the University of Utah School of Medicine. He also serves as a staff oncologist at the Veterans Administration Hospital in Salt Lake City, Utah. Weis specializes in the treatment of gastrointestinal cancer.

Weis served as research fellow in the lab of George Rodgers, MD, PhD, where he researched coagulation assays, induction/suppression of coagulant properties, tissue culture, and the relationship of atherogenic lipoproteins and thrombosis. He received his medical degree from the University of Minnesota in Minneapolis, and completed an internship and residency in internal medicine, as well as research and clinical fellowships in hematology/oncology, at the University of Utah. Prior to joining Huntsman Cancer Institute in 2001, Weis served patients through community practice for fifteen years.