Suppression cabin of marine reactor and marine reactor

The invention relates to the field of nuclear power ships and nuclear energy safety application, in particular to a pressure suppression cabin of a marine reactor and the marine reactor. The suppression cabin is an area defined by a containment inner wall, a reactor cabin outer wall and a reactor bottom plate and is divided into a gas cabin and a water cabin by a watertight deck, and the two ends of the watertight deck are connected with the side wall of the reactor cabin and the containment inner wall respectively; with the reactor cabin as a symmetric center, the watertight deck on one side of the reactor cabin is provided with an air hole, and the watertight deck on the other side is provided with a water falling hole; the vent hole is sequentially connected with a vent pipe, a drainage pipe and a return pipe, and the tail end of the return pipe is inserted into the cooling liquid; at least one layer of hysteretic deck is arranged in the water tank, and two ends of the hysteretic deck are respectively conn