Through the study of the theory of oil spill model, a mathematical modeling of oil spill on the sea is developed which with the consideration of spread, diffusion, drifting and attenuation of oil slick is influenced by evaporation and emulsification factors. A model that under the effect of ocean dynamic condition of tide, wind and wave, using Monte Carlo method to simulate the movement of oil slick is established. The modeling is applied to calculate and predict pollution range of oil spill at oil quay and oil ship in Daya Bay. The prediction results have basically shown the pollution situation by emergency of oil spill on the sea. Through the study of the theory of oil spill model, a mathematical modeling of oil spill on the sea is developed which with the consideration of spread, diffusion, drifting and attenuation of oil slick is influenced by evaporation and emulsification factors. A model that under the effect of ocean dynamic condition of tide, wind and wave, using Monte Carlo method to simulate the movement of oil slick is established. The modeling is applied to calculate and predict pollution range of oil spill at oil quay and oil ship in Daya Bay. prediction results have basically shown the pollution situation by emergency of oil spill on the sea.