The utility model discloses a plug -type gate system in construction building site, including the door body, set up the gatepost in door body both sides, the passageway of the push -and -pull door body is seted up to the inside of gatepost to and fix the slider in door body bottom, the door body at least including a door frame with the door plant on the door frame sets firmly, the door plant is in the outside of the door body, the gatepost includes the gatepost frame and sets firmly the gatepost board at gatepost frame surface that the gatepost frame is the truss structure, including four head trees and four little stands, the lower extreme of head tree is fixed subaerial, and the horizontal cross -section that four head trees enclose into the space is a rectangle, and four head trees are located rectangular cross section's summit respectively, four little stand settings form the passageway that the push -and -pull door was personally experienced sth. Part of the body in the space of being enclosed by four head trees, the lower extreme of little stand is above ground level, and it is as an organic whole with the head tree rigid coupling that little stand passes through the horizontal brace. This gate system saves space, and the dismouting of being convenient for is sturdy and durable, and it is recoverable to constitute the subassembly, satisfies green construction requirements.