Abstract: Because the remote sensing in monitoring the soil moisture and the crop evapotranspiration are of fleetness, macroscopic and convenient, the domestic and abroad scholars have studied great quantity researches in theory and technology field.This article analyse some research progresses and questions on land surface evapotranspiration by remote sensing, which can help the related workers.The result indicate covering in part vegetation, the estimate precision of two-layer model overtops the one-layer model obviously, but the two-layer model inject some parameters which increase the difficulty of arithmetic, so the two-layer model needs further study.