What was the name of House’s medical specialty department in House M.D.?

House’s department in House M.D. was called Diagnostic Medicine.

The department handled unusual cases that had resisted ordinary diagnosis. Dr. Gregory House led a small team of doctors who investigated symptoms, reviewed test results, and repeatedly revised their hypotheses.

Diagnostic medicine is a real medical field, but the show dramatized it as an unusually autonomous hospital unit. In real hospitals, difficult diagnoses generally involve collaboration among multiple specialties rather than one team performing every procedure.

The department’s cases often crossed specialties such as neurology, immunology, infectious disease, and oncology. That broad scope explains why House’s team could investigate rare conditions involving many different organ systems.