In order to solve the problems of poor accuracy and long time-consuming of traditional methods in the assessment of sudden oil spill pollution from ships, this paper takes the navigation area in the South China Sea as the research object and proposes to build the assessment model of ship oil spill pollution. Based on the analysis of the transportation advantages of the South China Sea navigation area, the probability of ship collision and the relationship between the probability of ship oil spill and the ship tonnage are obtained. Based on the probability of ship oil spill in the South China Sea navigation area, the evaluation index system of oil spill pollution in the South China Sea navigation area is constructed to determine the oil spill pollution index and pollution level, and to determine the oil spill pollution level The weight of oil pollution index is used to build the assessment model of sudden oil spill pollution in South China Sea navigation area. The experimental results show that the accuracy of the evaluation model is always maintained at 90% and the evaluation time is short.