For steel truss suspension bridges, traditional construction methods always have their disadvantages. This paper firstly points out the limitations of the traditional construction methods (such as the erection gantry method and the deck crane method). As the solutions, incremental launching method is proposed. Then, as an example based on a certain suspension bridge in Western China, non-linear analysis is carried out in order to illuminate how to decide the important parameters in practical application. Some further problems are discussed at the end.