USS Black Hawk was a large steamer purchased by the Union Navy during the American Civil War.

She was assigned by the Union Navy to gunboat duty in the waterways of the rebellious Confederate States of America.

Black Hawk, a side-wheel river steamer, was built in 1848 as Uncle Sam at New Albany, Indiana; purchased by the Navy at Cairo, Illinois, November 24, 1862 as New Uncle Sam; commissioned December 6, 1862, Lieutenant Commander K. R. Breese in command; and renamed Black Hawk December 13, 1862.

During most of her service Black Hawk served as flagship for Rear Admiral David Dixon Porter, Captain Alexander Mosely Pennock and Rear Admiral Samuel Phillips Lee, successive commanders of the Mississippi Squadron.

On April 22, 1865, she accidentally burned and sank, three miles above Cairo.