Abstract: The advance of research on surface sensible heat flux and latent heat flux was analyzed, ranging from experimental instruments to calculating model and to inversion of remote sensing. At present the instruments widely used include Bowen ratio, Eddy correlation techniques and Scintillometer. It is generally thought as constant flux layer over a homogeneous surface, therefore, flux data can be obtained from point measurements using Bowen ratio or eddy correlation techniques. However, over a heterogeneous land surface special techniques are necessary to estimate the area-averaged fluxes. In the case, scintillometers are used most widely and most effectively. Flux calculating models mainly include Eddy correlation, Bowen ratio, Energy balance and aerodynamic resistance model, Penman-Moteinth model, Priestley-Taylar, Dual sources model, and Surface Renewal model. Single-layer, two-layer and mult-i layer model of Energy-balance and aerodynamic resistance model are introduced. At the same time Surface Renewal model are described in detail. The images of remote sensing can give us rea-l time and rich surface information. As the advance of spatial, temporal and spectral resolution, the research on inversing surface flux by using remote sensing has become a hot topic. Now it is mainly based on the surface energy balance equation. Latent heat flux can be derived from inversing net radiance, soil heat and sensible heat flux. Finally, some hot topics in the research of surface flux were analyzed. They include (1) the usage of Bowen ratio on heterogeneous surface and under horizontal convection; (2) the research on greenbelt's ecological effect of cities based on flux; (3) scaling-up.

Key words: Surface flux, Experimental instrument, Calculating model, Inversion of remote sensing, Advance