The invention discloses a recoverable self-expanding flexible ureteroscope sheath, and belongs to the technical field of medical instruments, the recoverable self-expanding flexible ureteroscope sheath comprises a mounting seat, a through hole is formed in the middle position of the mounting seat, reset springs are uniformly fixed on the inner wall of the through hole, sheath wall plates are fixed on the reset springs, the sheath wall plates are attached to each other, and the sheath wall plates are fixed on the mounting seat. And air cavities are formed in the sheath wall plates, and strip-shaped pistons are arranged at the two ends of the interior of each air cavity in a sliding mode. Through the arrangement of the soft endoscope sheath composed of the four sheath wall plates, the air cavities in the sheath wall plates, the strip-shaped pistons and the connecting rods, in the using process, the soft endoscope sheath can be expanded and shrunk by inflating air into the air cavities, the PVC soft endoscope sheath can be bent due to the soft characteristic of the PVC soft endoscope sheath, and it is effectively avoided that in the operation process, the flexible endoscope sheath is not prone to being damaged; and moreover, the burden of a patient and the cost of seeing a doctor are reduced, the practicability is higher, and the use is more convenient.