Which fictional doctor is House M.D.’s closest friend?

James Wilson is Gregory House’s closest friend in House M.D.

Dr. Wilson is an oncologist at Princeton-Plainsboro Teaching Hospital and is played by Robert Sean Leonard. His medical specialty gives him a different perspective from House’s diagnostic work, while his more empathetic personality often counters House’s cynicism.

Wilson and House have a complicated friendship. Wilson repeatedly helps House despite frustration with House’s dishonesty, addictions, and disregard for rules. Their relationship is one of the show’s most important long-running storylines because Wilson understands House better than most colleagues do.

In the final season, Wilson is diagnosed with terminal thymoma, a cancer of the thymus. House responds by trying to spend Wilson’s remaining time with him, leading to the series finale’s central emotional conflict. James Wilson is sometimes confused with Robert Sean Leonard, the actor who portrays him.