The Special Boarding Unit (SBU) is a special forces unit established by the Japanese Maritime Self-Defense Forces on March 27, 2001. The unit was created to perform similar roles to those undertaken by American Navy SEALs and the British SBS. Its structure is based on the SBS. They are based in Etajima, Hiroshima.

Since the SBU is a special forces unit, any kind of matters regarding acquisition of information on personnel, training and weapons are forbidden since they are highly classified.  Its operators are seen publicly with balaclavas on to protect their identities.