The invention discloses a detachable floor support device comprising a movable support, a base and a buffer spring; the movable support comprises a supporting frame, auxiliary frames, fixing screws and sleeves; the supporting frame comprises a support disk and a locating column, and a neck, a groove, a connecting slot and rectangular slots are formed in the support disk; a four-angle special-shaped hole and guide holes are formed in the bottom of the groove; the connecting slot is separately connected with the four-angle special-shaped hole and the neck; four connecting holes are formed in thecircumference side of the locating column, and the connecting holes are internally provided with internal threads; the auxiliary frames are installed on the fixing screws through sleeves, and the fixing screws are separately matched with the connecting holes and the sleeves; and the base comprises a support cylinder and a base plate fixed to the support cylinder, the buffer spring and the locating column are installed in the support cylinder in sequence, and rectangular grooves are formed in the support cylinder. Through the movable support, the base, and combining with the buffer spring, thefunctions of supporting, buffering and adjustment for a floor can be achieved, at the same time, the impact of people on the ground is slowed down, and the functions of auxiliary adjusting and impactforce dispersing are achieved.