International Convention for the Control and Management of Ships Ballast Water and Sediments (Ballast Water Management Convention), which was implemented from 2017, requires the installation of a ballast water management system (BWMS) for international shipping line vessels of 400 gross tons and above. Ballast Water Management Convention requires the installation of ballast water treatment equipments for ships on international routes. But there is a condition that vessels absolve installation of BWMS in the A-4 clause of the ballast water convention. In order to meet the requirements of the Convention of Ballast water convention and reduce the investment of Chinese and Korean routes in the Yellow Sea waters, In recent years, China and South Korea have used academic exchanges and technical assessments to analyze the biological invasion risks caused by the discharge of ballast water in the yellow sea. In this study, the risk assessment of biological invasion was carried out using the Same Risk Area method firstly proposed by Denmark and Interferry. The Same Risk Area Method is adopted for risk assessment. The two dimensional hydrodynamic model of the Yellow Sea and Agent Based Modelling are established, the natural biological diffusion was simulated by the release of Skeletonema costatum, the effects of water temperature and salinity on biological behavior were coupled. The simulation results show that the port waters between China and South Korea has certain natural diffusion connectivity. But the connectivity between test ports cannot be determined from time and space, and the Yellow Sea Large Marine Ecosystem is not a Same Risk Area.