To investigate the structure and evolution characteristics of urban breeze circulation in the mountain city, WRF V3.9 is used to simulate a typical urban breeze circulation case from August 17 to 18, 2016 in Chongqing. In addition, the characteristics of turbulent kinetic energy and turbulent fluxes during this period are also analyzed. The results show that the rural wind begins to appear at 15:00 and increases as the heat island strengthen. The circulation reaches its maximum at 18:00, and is destroyed at 02:00 in the next day. At 18:00, the horizontal scale of the circulation is about 1.5~2 times that of the urban scale, and the vertical scale is about 1.3 km, the horizontal wind speed is about 2~4 m?s-1, the maximum rising speed is about 0.5 m?s-1. Under the influence of topography, rivers and background wind, the circulation is asymmetrical in structure and weak in intensity. Besides, it is found that the turbulent kinetic energy in the urban area is obviously larger than that in the nonurban area, which results in the stronger transport of heat and water vapor by turbulence in the urban area. When it comes to the relationship between turbulent fluxes and urban breeze circulation, it shows that turbulent water vapor flux is affected by urban breeze circulation obviously, turbulent supply momentum for the dissipation caused by urban breeze circulation.