To explore the Characteristics of Land Surface Water-heat Zxchange over Gyaring Lake and Ngoring Lake in Summer， the new generation of mesoscale numerical model WRF（Weather Research and Forecasting Model）， developed by National Centers for Environmental Prediction（NCEP） and National Center for Atmospheric Research （NCAR） was used to simulate the characteristics of atmospheric boundary layer in Gyaring and Ngoring Lakes area.The results show that the WRF model can preferably simulate the diurnal variation characteristics of 2 m height temperature， sensible heat and latent heat flux.Gyaring and Ngoring Lakes have great cooling （heating） effect to the air above lakes during the day （night）， showing obvious cold （warm） lake effect， and producing temperature difference between lakes and land.Such a temperature difference will affect the local wind field.during the day， in the central area of Gyaring and Ngoring Lakes have the strength of 1.0 m·s^-1 and 0.5 m·s^-1 of downdrafts respectively， and an updraft of 2.5 m·s^-1 in intensity appeared over the surrounding area.The effect of Gyaring and Ngoring Lakes on sensible heat and latent heat during the day and night varies greatly.The existence of the two lakes will make the sensible heat and latent heat value of the lake surface lower than the surrounding land during the day， while the effect of the two lakes on sensible heat and latent heat at night is opposite to that of the daytime.For the height of atmospheric boundary layer， the existence of Gyaring and Ngoring Lakes effectively reduces the height of atmospheric boundary layer over the lake area during the day， but the influence of Gyaring and Ngoring Lakes on the height of atmospheric boundary layer is not obvious at night.