The main bridge of Longxiang Bridge is a combination system of large-span double main span continuous rigid frame with steel beams as the mid-span joint section. Based on the construction of the main bridge of Longxiang Bridge, a new lifting system was proposed, which realized the rapid transformation of three construction stages: cantilever beam construction, steel-mixed section lifting and large-section mid-span steel beam lifting. The strength, stiffness and stability checking calculation of the lifting system at each stage of construction are analyzed by finite element method, and compared with the measured displacement data of the steel beam hoisting with large segment span, which verifies that the lifting system can meet the requirements of construction efficiency, safety and quality, and provides reference experience for similar bridges in the construction and closing process.