Advances in remote sensing (RS) technology provide an effective approach for the estimation of regional evapotranspiration, crop classification and yield, which lays the foundation for the quantitative assessment of irrigation efficiency and crop water use efficiency. Relevant models and methods were reviewed, including RS-based evapotranspiration models, upscaling methods of instantaneous evapotranspiration to daily evapotranspiration, interpolation methods of available daily evapotranspiration, RS-based crop classification methods and crop yield estimation models, and assessment methods for irrigation efficiency and crop water use efficiency based on evapotranspiration and crop yield estimations. Furthermore, key issues that require further investigation were proposed, including RS-based evapotranspiration model with strong physical bases and applicable to heterogeneous land surfaces, proper interpolation method of daily evapotranspiration considering the abrupt change of soil water content due to irrigation and/or precipitation, precise estimation of irrigation water consumption in farmland evapotranspiration, RS-based crop classification model applicable to complex cropping pattern and multi-years, and operational RS-based crop yield estimation model with higher precision. With further developments of RS technology and relevant models, the quantitative assessment results of irrigation water use efficiency and crop water use efficiency will provide sound foundation for agricultural water management.