Thomas Crook Sullivan (November 14, 1833 – March 11, 1908) was a brigadier general in the United States Army.

He was later ordered to Washington (D.C.), arriving in the Winter of 1861, and selected as a guard for president-elect Abraham Lincoln during his first inauguration.

He served throughout the American Civil War and was brevetted major and lieutenant colonel on March 13, 1865, for "faithful and meritorious service".

The entire garrison of officers and enlisted men turned out and gave honors and services while his remains lay in state at Fortress Monroe chapel.

He is buried in one of only two mausoleums in Arlington, the other being that of Lieutenant General Nelson Appleton Miles in Section 3.