Abstract: With the expanding of natural gas pipeline networks, the topological structures get more and more complicated and the demanded computation and time consumption in the process of pipeline-network transient simulation increase sharply. To solve this problem, a high-efficiency simple simulation method FS-D&C was proposed according to the divide-and-conquer concept. Firstly, all connection nodes between the components of natural gas pipeline network are solved. Secondly, the pipeline network is divided into several independent pipelines. Thirdly, the hydraulic and thermal parameters of each pipeline are solved one after another. The connection nodes and the pipelines are solved by the conjugate gradient (CG) method and the tridiagonal matrix method, respectively. The proposed method based on divide-and-conguer concept and SPS software was compared in a case. The FS-D&C method can be implemented simply with the calculation accuracy as high as SPS but the calculation speed 1.5 times faster than SPS. The method has strong adaptability to the simulation of pipeline networks as well as SPS, and is even much stronger when the network size becomes larger.