Firstly, a discrete equation of motion of free spanning submarine pipeline was derived. The spatially varying earthquake ground motions, the internal pressure and the thermal load were imposed on the FE model. The nonlinear material constitutional relationships of the pipe and the soil as well as the large displacement effect were considered. Secondly, the numerical results were compared with the experimental results in order to validate the kind of pipe element employed in the analysis. Thirdly, the effects of internal pressure, thermal loading and the interaction between pressure and temperature on the multi-support input response of the submarine pipelines were studied respectively.