USS Shepherd Knapp (1861) was a large (838-ton) ship with eight guns, purchased by the Union Navy during the beginning of the American Civil War. With her eight guns and a crew of 93, she was employed by the Union Navy as a heavy gunship outfitted to pursue major Confederate States of America blockade runners, especially Confederate Captain Raphael Semmes. During the course of her fruitless searches for Semmes, she ran aground on a reef near Haiti and was abandoned.