Dr. Xu completed his medical degree in 1986, and then became a lecturer in microbiology at the Yanbian Medical College, China. In 1991, he moved to the US and started to work as a research scientist in the virology department at the NYS Institute for Basic Research on Staten Island. In 2007, following residency and chief residency in pediatrics at the St. Vincent Medical Center, he joined a fellowship in pediatric gastroenterology, hepatology, and nutrition at SUNY Downstate Medical Center at Brooklyn, where he became full-time faculty as an assistant professor.
In 2017, he returned to RUMC and became program director of the residency program and chief of gastroenterology in the department of pediatrics. His research portfolio and interest include both basic science (molecular biology and gut immunology) and clinical gastrointestinal disorders (inflammatory bowel disease, necrotizing enterocolitis, hepatitis B, parenteral nutrition-associated liver disease and nonalcoholic fatty liver disease).