The Hajen class, also known as the Hajen III class, was a series of submarines built by Kockums and operated by the Swedish Navy. The design was influenced by the German Type XXI submarine. A total of six submarines were built between 1954 and 1958 and were kept in service until 1980.
The first Hajen-class submarine to be built was in 1954, followed by (1955), (1955), (1957), (1958), and (1958).