Abstract: The method to lay pipeline in tunnel for some pipeline section of Zhongxian-Wuhan Gas Transmission Pipeline is introduced. This paper analyzes the stability of the pipeline section installed in tunnel, including the stability with the continuous beam laying way, the span and axial stability when the beam is stressed as well as the stability of pressured pipeline section with pipe laying in embankment way, calculates the individual span length of section and critical length of the stressed beam. The authors consider that the best way to lay pipeline in tunnel can be selected after the stressed boundary conditions of pipeline installed determined.