In order to research the distribution of thermal field of low temperature discharge from LNG in the ocean, further to formulate reasonable wastewater marine disposal scheme and provide scientific support to the protection of ocean environment, a two-dimensional hydrodynamic model was used to simulate the tide current field in the radial sand ridge group of shallow sea area of Jiangsu maritime space. This model was based on the tide current characteristics near the LNG project and the seasonal design of the typical hydrological conditions in different seasons. This model was used as the hydrodynamic condition that simulated the transport and diffusion for the heat quantity in the change of time and spatial distribution. Considering the comprehensive heat radiation coefficient of water surface, the 2-D water temperature model was established to predict the spatial distribution and temporal variation of the temperature field in the receiving waters. Finally, results showed that the low temperature drainage less affected in the ocean water environment.