HMS K6 was a British K class submarine built by HM Dockyard, Devonport.

K6 was the first of the K class to have its bows raised by converting it into a bulbous swan shape.

[2] The submarine was powered by two oil-fired Yarrow Shipbuilders boilers supplying one geared Brown-Curtis or Parsons steam turbine; this developed 10,500 ship horsepower (7,800 kW) to drive two 7 ft 6 in (2.29 m) screws.

Submerged power came from four electric motors each producing 350 to 360 horsepower (260 to 270 kW).

[2] Its torpedo tubes were fitted to the bows, the midship section, and two were mounted on the deck.