Construction method of back-pull large-cantilever steel structure roof

The invention relates to the technical field of building construction, and discloses a back-pull large-cantilever steel structure roof construction method which comprises the following construction steps: fixedly mounting a core tube on a concrete stand; the pipe truss is fixedly installed at the top end of the core tube; an outer side cantilever is fixedly installed on the side, close to the outside, of the pipe truss, and the side, away from the pipe truss, of the outer side cantilever is pulled in the direction of the concrete stand; the first temporary support is installed in the venue; an inner side cantilever is fixedly installed on the side, close to the field, of the pipe truss, and the end, away from the pipe truss, of the inner side cantilever abuts against the first temporary support; and after the inner side cantilever is installed, the first temporary support is detached and removed. The outer overhang can be pulled, the weight needing to be borne by the core tube is shared, the roof can be suppo