Abstract: Based on the theory of linear dual-source evapotranspiration (ET) model,this paper develops a remote sensing model for estimating the land surface ET.The remote sensing model has two characteristics: to (1) simplify the VITT method and improve the accuracy of determining soil water status in a semiarid irrigation area,and (2) introduc the dual-source model in calculating land surface ET and improve the calculation accuracy of the mixed pixels.The remote sensing model is applied for calculating the land surface ET about a 1 000 km² in North China Plain by using 13 Landsat TM and ETM+images during the period 2000-2002.It is illustrated that the remote sensing model based on dual-source linear concept can get good estimates when applied in semiarid irrigated area.