The application belongs to the technical field of steel structure roof truss installation, in particular to a quick installation auxiliary device for steel structure roof truss installation, comprising a plurality of vertical steel beams and a crane, the vertical steel beams are arranged in
linear array on the ground, the upper end surfaces of all vertical steel beams are jointly provided with a frame-shaped plate, a composite truss is arranged above the frame-shaped plate, the composite truss is hoisted to above the frame-shaped plate by the crane, a fastening mechanism is arranged at the bottom of the crane, the fastening mechanism is used for fastening the two side surfaces of the frame-shaped plate, the fastening mechanism comprises a connecting
rope installed above the crane; the fastening mechanism can automatically take out the connecting
rope from the surface of the composite truss, without the need for workers to manually untie the connecting
rope, the operation is relatively safe, convenient and fast, which is beneficial to the installation of the composite truss, and the hoisting mode of the remaining composite trusses is also the same, so that they are arranged in
linear array above the frame-shaped plate, so that the roof truss can be quickly installed.