Lower limb rehabilitation exercise device

The utility model belongs to the technical field of medical instruments, and discloses a lower limb rehabilitation exercise device which comprises a CPM main body, the bottom of the CPM main body is connected with a fixing rod, the side of the CPM main body is provided with a sliding groove, the CPM main body is connected with a supporting assembly, the supporting assembly slides along the sliding groove, the CPM main body is fixedly connected with a pneumatic pump, the pneumatic pump is fixedly connected with a handle, and the handle is fixedly connected with the CPM main body. The top end of the supporting assembly is connected with a shank supporting frame, the shank supporting frame is connected with a shank air bag, the shank air bag is in pipe connection with a first air conveying pipe, the free end of the first air conveying pipe is in pipe connection with a pneumatic pump, one end of the shank supporting frame is hinged to a thigh supporting frame, the thigh supporting frame is connected with a thigh