Packaging box lining assembling jig

The utility model discloses a packing box lining assembling jig, which belongs to the technical field of packing box lining assembling equipment and comprises a fixing frame, a sliding seat is slidably mounted in the middle of the fixing frame, the front end of the sliding seat is fixedly connected with a limit block, a guide frame is slidably mounted on the rear portion of the sliding seat and penetrates through the sliding seat, and the limit block is fixedly connected with the guide frame. A reset spring is fixedly connected between the guide frame and the sliding seat, a two-way threaded rod is rotationally connected into the guide frame, positioning frames are symmetrically installed outside the two-way threaded rod in a threaded mode, air between the sealing cover and the lining is sucked through the air suction holes, the lining is tightly sucked and fixed to the sealing cover, then the positioning frames are sleeved with a target packaging box, and then the target packaging box is placed in the positi