The invention relates to a seating device attached to a body. The seating device comprises a seating surface, conical supporting seats, spring pieces, at least three connectors, at least three stand rods and elastic reset parts; the supporting seats are hinged to the left end and the right end of the seating surface respectively, and the inner top ends of the supporting seats are provided with pull rods coaxial with the supporting seats; the left end and the right end of the seating surface are further each provided with a hanging belt, and the ends of the hanging belts are provided with hooks; each spring piece comprises a base and at least three installation supports, the installation supports can be mutually opened and closed, and the bases are installed on the pull rods in a sleeving mode, can slide relative to the pull rods and are limited through limiting blocks arranged at the ends of the pull rods; the stand rods are installed on the lower portions of the corresponding connectors, and the upper portions of the connectors are installed on the corresponding installation supports; the elastic reset parts are installed on the connectors and used for resetting the connectors. The seating device can be moved along with the body, achieve the purpose of immediately sitting down to have a rest and allow field or outdoor operating personnel to use and is stable in support.