Mayasan Maru (摩耶山丸) was a Japanese landing craft depot ship used extensively to transport Imperial Japanese Army (IJA) troops during 1943 and 1944. After avoiding damage in seven separate submarine attacks in earlier convoys, she was sunk in the East China Sea by the submarine USS Picuda on 17 November 1944 while part of Convoy Hi-81. The sinking caused one of the highest maritime casualty counts of World War II. Some 3,536 people died.