The Shinkai 6500 (しんかい) is a crewed research submersible that can dive up to a depth of 6,500 metres (21,300 ft).

The Shinkai 6500 is owned and run by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) and it is launched from the support vessel Yokosuka.

[1] Two pilots and one researcher operate within a 73.5 mm-thick (2.89 in) titanium pressure hull with an internal diameter of 2.0 metres (6 ft 7 in).

[2] Buoyancy is provided by syntactic foam.

[3] Three 14 cm (5.5 in) methacrylate resin view ports are arranged at the front and on each side of the vehicle.