The invention discloses a method of constructing a steel-concrete composite steel beam adopting a crossing type inhaul cable. The method includes the steps that firstly steel beam units are prefabricated, a plurality of temporary suspension pieces are arranged at the steel beam bottom plates, inhaul cable devices are correspondingly arranged at bridge steel beam erection machines simultaneously, after a first steel beam crossing the bridge opening is erected to be on position, suspension clasps at the bottom portions of the inhaul cables of the bridge steel beam erection machines and the suspension pieces of the steel beam bottom plates are mutually connected in a crossing mode to enable the inhaul cables of the midspan area to form a crossing cable-stayed condition; then the inhaul cablestress is stretched to a preset value to be locked; prefabricated concrete bridge deck slabs are installed; bridge deck slab wet joint concrete are poured; when the bridge deck slab wet joint concreteachieves the designed strength, the connection of the inhaul cables and the suspension pieces are relieved; a second steel beam crossing the bridge opening is erected, the construction of steel beamscrossing the two bridge openings is completed; and in turn, the construction of the whole bridge is completed. According to the method of constructing the steel-concrete composite steel beam adoptingthe crossing type inhaul cable, the material using efficiency of traditional non-bracket construction steel-concrete composite steel beam can be improved, the convenient and rapid construction and aseries of advantages are possessed, and wide application prospects in large and middle span composite beam erection are possessed.