Article · Wikipedia archive · Last revised Jul 30, 2026

JS Yoshii

JS Yoshii is the 12th and last ship of the Mogami-class frigates of the Japan Maritime Self-Defense Force. She is named after the Yoshii River in the Okayama Prefecture, a name that had not been previously used by the Imperial Japanese Navy.

Last revised
Jul 30, 2026
Read time
≈ 2 min
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397 w
Citations
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Source
Wikipedia ↗
Yoshii during her launch ceremony
History
Japan
NameYoshii
NamesakeYoshii River
BuilderMitsubishi Heavy Industries Nagasaki Shipyard
CostApproximately 46 to 47 billion yen
Laid down3 July 2024
Launched22 December 2025
CommissionedFiscal year 2026 (scheduled)
IdentificationFFM-12
StatusFitting out
General characteristics
Class & typeMogami-class frigate
Displacement
  • 3,900 t (3,800 long tons; 4,300 short tons) (standard)
  • 5,500 t (5,400 long tons; 6,100 short tons) (full load)
Length132.5 m (434 ft 9 in)
Beam16.3 m (53 ft 6 in)
Draft9 m (29 ft 6 in)
Propulsion
Speed30 knots (56 km/h; 35 mph)
Boats & landing
craft carried		2 × RHIB, UUV, USV
Crew90-100
Sensors &
processing systems
  • OPY-2 (X-band multi-purpose AESA radar)
  • OAX-3(EO/IR)
  • OQQ-25 (VDS + TASS)
  • OQQ-11 (Mine-hunting sonar)
  • OYQ-1 (Combat management system)
  • OYX-1-29 (Console display system)
Electronic warfare
& decoys		NOLQ-3E (Passive radar system + Electronic attack capability is integrated into the main radar antenna), Chaff dispenser
Armament
Aircraft carried1 × SH-60K patrol helicopter

JS Yoshii (Japanese: よしい; Hull Number: FFM-12) is the 12th and last ship of the Mogami-class frigates of the Japan Maritime Self-Defense Force. She is named after the Yoshii River in the Okayama Prefecture, a name that had not been previously used by the Imperial Japanese Navy.12

Construction and career

Yoshii was laid down in July 2024, at the same time as her sister ship Tatsuta.2 The ship was launched at Mitsubishi Heavy Industries' Nagasaki Shipyard on 22 December 2025, with Minister of Defense Shinjiro Koizumi attending the ceremony.12 The combined construction cost for both Yoshii and Tatsuta was approximately 116.6 billion yen. Yoshii is scheduled to be commissioned in the fiscal year 2026.1

References

References

  1. "海上自衛隊の新護衛艦　岡山県東部流れる吉井川由来「よしい」に　吉井川由来の艦艇名は初めて【岡山】" [The Japan Maritime Self-Defense Force's new escort ship will be named "Yoshii," a reference to the Yoshii River that flows through eastern Okayama Prefecture. This marks the first time a vessel has been named after the river.]. Yahoo! News Japan (in Japanese). 22 December 2025. Archived from the original on 22 December 2025. Retrieved 22 December 2025.
  2. "小泉進次郎防衛相も臨席！ 海自最新のステルス護衛艦「よしい」進水 史上初の艦名その由来は？" [The 12th Mogami-class ship is named after a river in Okayama Prefecture.]. Traffic News (in Japanese). 22 December 2025. Retrieved 22 December 2025.