Based on computational fluid dynamic，a fluid solid coupling heattransfer model of submarine in two areas was built，which were respectively the area on seawater and the sea mud area，and the sea mud area was disposed of saturated silt porous. Using the software, the leakage during the process of transmission on naked placed hot oil pipeline was simulated, and the changes of distribution of crude oil in the soil and the water of the sea and the changes of the temperature field were analyzed，and different leakage points were analyzed respectively. The settlement of its own of the submarine pipeline on the naked place and the effect of the pressure in the sea water were considered in the simulation. The simulation results showed that different leakage points had a different influence on the distribution of crude oil|when the leakage in the sea mud area happened，the distribution of crude oil in the sea mud was a arcshape, after a period of time, the crude oil flowed into the sea long the sea mud and pipe insulation, and the top was a sprayshape and the flanks was helix, finally the crude oil flew onto the surface of the sea|when the leakage point was located in the sea area, oil was jet diffusion distribution form and under the action of buoyancy, the crude oil flow gradually onto the sea. As the leak position was different，the water of the sea and the sea mud there had significant differences in the distribution of temperature field. The interface of sea water and sea mud areas had a great impact on the temperature field distribution of crude oil.