America Maru (亜米利加丸, Amerika-Maru) was the second of three high speed passenger liners built for the Oriential Steamship Company (Tōyō Kisen). Converted into an armed merchantman during the Russo-Japanese War of 1904–1905, she played a crucial role in the Battle of Tsushima. Although used as a hospital ship during the early part of World War II, she had been chartered by the Imperial Japanese Navy as a transport in 1943, and was sunk by the United States Navy in 1944 with great loss of civilian lives.

Asano Sōichirō, owner of the Asano zaibatsu, decided that he wished to create a shipping company, and founded Tōyō Kisen in July 1896. With the assistance of the Pacific Mail Steamship Company, orders were placed with the Wigham Richardson shipyards at Newcastle upon Tyne in England for three vessels. Asano's stipulation was that the vessels have the clean, sharp lines of clipper ships, and were to be painted white. Up until this time, Japanese shipping companies mainly concentrated on local traffic with China. However, Asano intended to compete against the Pacific Mail Steamship Company, Canadian Pacific, and other foreign shippers on trade to India and Europe, as well as North America.

America Maru was laid down in March 1897, launched on March 9, 1898, and completed on September 24 of the same year.

On her maiden voyage, America Maru called at Hong Kong – Xiamen-Shanghai – Nagasaki – Yokohama – Kobe and on to Honolulu and San Francisco. With her sister ships, Nippon Maru and Hong Kong Maru, she was placed into scheduled services on the north Pacific Route. Upon docking in Honolulu in October 1899, America Maru was suspected of bringing rats with the bubonic plague to Hawaii and was placed in quarantine by American authorities. In an effort to control the epidemic, Honolulu's Chinatown was burned down.

In December 1900, noted author and physician Hideyo Noguchi travelled to the United States aboard America Maru. In June 1901, after Kuomintang leader Sun Yat-sen's revolt against the Qing dynasty failed, he fled to Japan aboard America Maru, which was in Tianjin conveying supplies to Japanese forces involved in the suppression of the Boxer Rebellion.

With the start of the Russo-Japanese War in February 1904, America Maru was requisitioned by the Imperial Japanese Navy (IJN) for use as an armed merchant cruiser and began conversion at Yokosuka Naval Arsenal on 15 February 1904. However, a fire aboard the ship caused severe damage, and she was not ready for use until February 1905.

Under the command of Captain Ishibashi Hajime in April 1905, she was based at Tsushima Island as one of seven armed merchantmen and three torpedo boat tenders assigned to patrols of the Tsushima Strait to search for the Russian Baltic Fleet, which had been dispatched around the world to relieve the Japanese blockade of Port Arthur. On the night of May 26–27 Shinano Maru, America Maru, Sado Maru and Manshu Maru were deployed as a lookout screen in the strait between Gotō Islands and Jeju-do. Shinano Maru's early contact with the Russian fleet was a major contributing factor in the decisive Japanese victory at the Battle of Tsushima.

After the battle, America Maru located the sinking wreckage of the Russian protected cruiser Svetlana and rescued 291 survivors.