
The JMSDF changed its naming convention with the Sōryū, and submarines will now be named after mythological creatures. Japanese submarines since World War II were named after ocean currents. In 2019, the replacement to the Sōryūs, the Taigei-class submarine, entered the planning phase. The cost of the sixth submarine ( Kokuryū) was estimated at 540 million USD. Furthermore, Ōryū is the world's first lithium-ion battery submarine. From Sōryū to Shōryū are fitted with Kockums Naval Solutions Stirling engines license-built by Kawasaki Heavy Industries, allowing them to stay submerged for longer periods of time. It is Japan's first air-independent propulsion submarine. The Sōryūs have the largest displacement of any submarine used by post-war Japan.

The design is an evolution of the Oyashio-class submarine, from which it can most easily be distinguished by its X-shaped stern combination diving planes and rudders. The first boat in the class entered service with the Japan Maritime Self-Defense Force in 2009. The Sōryū-class submarines ( 16SS) are diesel-electric attack submarines. 6 × HU-606 21 in (533 mm) torpedo tubes with 30 reloads for:.2× 3-inch underwater countermeasure launcher tubes for launching of Acoustic Device Countermeasures (ADCs).Hughes/Oki ZQQ-7 Sonar suite: 1× bow-array, 4× LF flank arrays and 1× Towed array sonar.ZPS-6F surface/low-level air search radar.4× Kawasaki Kockums V4-275R Stirling engines - up to ShōryūĪIP endurance (est.): 6100 nautical miles (11297.2 km 7060.75 miles) at 6.5 knots (12 km/h 7.48 mp/h).1-shaft 2× Kawasaki 12V 25/25 SB-type diesel engines diesel-electric.Hakuryū (SS-503) visits Pearl Harbor, Feb 2013
