Abstract: Regarding the study of transient operations for buried hot oil pipelines, resulted from changes of throughput and heating temperature, the mathematical model, where the flux between the outer wall of pipeline and soil acts as the coupling parameter, is put forward and one simple and effective method to calculate the flux is also presented in the paper. On the basis of examples, the rationality of the model and method is proofed according to the contrast and analysis between actual data and calculated results, which provides a new idea to the future study of transient problems for buried hot oil pipeline.