The Yūshio was a Japanese diesel-electric submarine class operated by the JMSDF. It was a second generation submarine, a development of the Uzushio class submarine, incorporating a teardrop hull, with a resulting increase in underwater performance on the Uzushio class submarine. Ten were built under the fourth defense plan in 1975 fiscal year. A training submarine, Yukishio, was retired on March 7, 2008. All warships were retired on the completion of the Harushio class submarine.