Etorofu-class escort ship

The Etorofu-class escort ships (択捉型海防艦) were a class of ships in the service of the Imperial Japanese Navy during World War II.

The Japanese called these ships Kaibōkan, "ocean defence ships", (Kai = sea, ocean, Bō = defence, Kan = ship),  to denote a multi-purpose vessel. The fourteen ships of the Etorofu class were a major part of Japan's escorts from the middle of World War II. They were denoted "Improved Type A" ships, and were the second class of Kaibōkan. The Etorofus, unlike the, received more emphasis on submarine warfare.

The Etorofu class was initially armed with thirty-six depth charges and would later rise to 60 depth charges with an 8 cm trench mortar and six depth charge throwers. The rise of aircraft also saw the number of AA machine guns increase to 15. They would receive Type 22 and Type 13 radars and Type 93 sonar in 1943-1944.

The ships of the class were the JAPANESE ESCORT SHIP Etorofu (択捉), Hirato (平戸), JAPANESE ESCORT SHIP Tsushima (対馬), Fukae (福江), JAPANESE ESCORT SHIP Matsuwa (松輪), Mutsure (六連), Sado (佐渡), Oki (隠岐), Manju (満珠), Kanju (干珠), Iki (壱岐), JAPANESE ESCORT SHIP Amakusa (天草), Wakamiya (若宮), and Kasado (笠戸).

Eight of the fourteen ships, Hirato, Iki, Amakusa, Kanju, Wakamiya, Sado, Mutsure, and Matsuwa were sunk during the war.