Abstract: The numerical method to study and determine the shut down and temperature drop process for buried hot oil pipeline is introduced, in which the 3 mathematical models, the inside hot oil model, outside insulator of pipe model and outside soil temperature field model are adopted to study the process of shut down and temperature drop of hot oil pipeline. It is pointed out that after non-insulating hot oil pipeline is shut down, the temperature of oil within the pipe and soil outside the pipe drop simultaneously and there is temperature drop affecting zone outside soil, while after the insulating hot oil pipeline is shut down, the velocity of temperature drop of hot oil is obviously lower than non-insulating pipeline.