The disclosure discloses a solid fluidization tubular separator for marine natural gas hydrate, which includes a first separator and a second separator, wherein the first separator includes the first separation sleeve, the power liquid pipe, the swirl baffle, the recovery mechanism and the sand discharge mechanism. After the hydrate is sucked into the first separation sleeve to generate a circumferential velocity, so that the mud and sand with high density are separated to the pipe wall of the first separation sleeve, and the mud and sand separated to the pipe wall are settled down from the gap between the swirl baffle and the pipe wall along the pipe wall. The hydrate swirl flows into the recovery mechanism, and then leaves the first separation sleeve and enters the second separator, so as to realize the separation of mud and sand and natural gas hydrate.