Abstract: Based on a coupled convection-diffusion and hydrodynamic model, the distribution of petroleum hydrocarbons (Phs) in that year was simulated using total Phs from seagoing rivers and platforms in 2010 in Bohai sea.The sharing rate of separate main seagoing rivers and platforms and their impact on Bohai Phs are also computed and discussed in this paper.The results shows:the concentration of Phs in Laizhou bay is among 20~80 g/L, 13~15 g/L in Bohai bay, 8~10 g/L in Liaodong bay, and 2~10 g/L in the central part of Bohai sea; Yellow River shares the highest rate(60%)in Laizhou Bay, also in Bohai Bay, Yellow River gets 30%~50% of share rate, and Liao river occupies 20%~60% share rate in Liaodong Bay, Yellow River shares the highest rate(20%~50%)in the central part of Bohai sea. The share rate of oil platforms is less than 10% in Laizhou Bay, 10% to 20% in Bohai Bay, 20% to 30% in Liaodong Bay and 10% to 30% in the central part of Bohai.