The K-129 was a Russian diesel-electric-powered ballistic-missile submarine that served in the Pacific Fleet of the Soviet Navy. This was one of six Project 629 strategic ballistic-missile submarines assigned to the 15th Submarine Squadron based at Rybachiy Naval Base near Petropavlovsk.
The K-129 was launched on 16 May 1959. Nearly 9 years later, she sank on 8 March 1968 with the loss of all 98 crew.