The invention discloses a large-diameter silo structure roof construction method. The large-diameter silo structure roof construction method includes the steps of: (1) pre-burying a lifting frame andopening a hole when the construction of a silo reaches the top, placing the hole into an embedded bailey frame, and then burying a corbel on top of a silo wall; (2) using the lifting frame to lift a ground bailey frame to the top of the bailey frame, and docking the ground bailey frame with the embedded bailey frame to form a bailey frame system; (3) connecting a main beam on the bailey frame system, laying a panel on the main beam to form a working platform, and finally installing a roof pouring support system. The large-diameter silo structure roof construction method has the advantages thatwith the lifting frame pre-buried and the hole opened when the construction of the large-diameter silo reaches top, the hole placed in the embedded bailey frame, the ground bailey frame lifted by thelifting frame and the bailey frame system formed through the docking between the ground bailey frame and the embedded bailey frame, and the bailey frame system constructed separately, the setting upof the roof pouring support system is fast and highly efficient, and due to the fact that formwork and the roof pouring support system are delivered to the ground by the separating of the drooping ground bailey frame during the demolition, demolition is fast and safe.