What is James Wilson’s profession in House M.D.?

James Wilson is an oncologist in House M.D.

Wilson, played by Robert Sean Leonard, heads the hospital’s Department of Oncology and treats patients with cancer. He is also Gregory House’s closest friend and one of the few people willing to challenge House personally as well as professionally.

The friendship between Wilson and House is one of the show’s main relationships. Wilson often supplies emotional judgment and practical advice, while House tests the limits of Wilson’s patience. Their contrasting personalities—House’s cynicism and Wilson’s empathy—create both humor and dramatic tension.

Wilson’s specialty is sometimes confused with general internal medicine because he interacts with many departments at Princeton-Plainsboro. Oncology specifically concerns cancer, including its diagnosis, treatment, and management. The character’s medical role becomes especially important in the final season, when his own health changes the direction of the series and its ending.