The vessel departed Kobe with Bungo and Tokiwa on 23 September 1999 to transport temporary housing as an aid to the damage caused by the northwestern Turkey earthquake that occurred on 17 August.

[2] The first long-distance continuous voyage in the history of the Maritime Self-Defense Force was carried out to Alexandria at an average speed of 18 knots (33 km/h; 21 mph) for 23 consecutive days without calling, and arrived at the port of Heidalpasha in Istanbul on 19 October.

From 26 to 28 January 2010, special transportation training was conducted at Sasebo and the waters west of Kyushu together with Kunisaki and USS Tortuga.

[3] From June to July 2012, she participated in the Pacific Partnership 2012, visited the Philippines and Vietnam, and engaged in medical activities and cultural exchanges.

For nine days, beginning on 5 May 2018, Ōsumi participated in multilateral joint training on humanitarian assistance and disaster relief organization with the Indonesian Navy off Lombok island.

[13] From 5 to 19 October, Ōsumi took part in Japan-US joint training that was conducted in Tanegashima, Kagoshima Prefecture and the surrounding sea and airspace.