Abstract: Based on the mechanism of sea-land breeze circulation and its formation of physical model, the numerical simulation model was established. According to the above-mentioned, the diurnal variations of atmospheric press field, velocity field, temperature field and turbulent kinetic energy field were simulated. The daily variations of solar radiation and ground energy as well as turbulent kinetic energy were described. The horizontal turbulent diffusion coefficient of sea-land breeze and the vertical turbulent diffusion coefficient of momentum, temperature and turbulent kinetic energy were simulated, which can provide the reference for solving the pollutant diffusion concentration of sea-land breeze in order to estimate the loss of environmental pollution. Sea-land breeze circulation in Dalian was simulated by this method, and the distributions of velocity, press, temperature and turbulent kinetic energy and other related parameters were analyzed quantitatively and qualitatively. The results indicate that the local diurnal variation of atmospheric press field of sea-land breeze circulation is small, while the variation of temperature field is evident. The maximum values of vertical turbulent diffusion coefficient of momentum, temperature and turbulent kinetic energy appear at noon. Compared with the simulation results from the literatures, the results from this model accord with the results from the experiments. However, the prediction accuracy should be further tested.