Abstarct: Evapotranspiration (ET) is one of the important parameters for agriculture water management. Evapotranspiration is one of the most significant sources for water loss in a watershed and hence. monitoring and assessing its temporal and spatial changes can also show the amount of water consumption for various land uses and also utilized for basin-scale water management and water to various sectors and land-uses. Because of several difficulties in measuring its value directly, many methods have been proposed to estimate ET indirectly, baxsed on meteorological data at weather stations. Due to spatial changes of meteorological parameters and consequently ET value, some algorithms which are baxsed on remotely sensed data have been developed in the past few decades. Surface energy balance algorithm (SEBAL), is one of the most widely-used algorithms for estimating evapotranspiration using satellite images. The purpose of this study was to assess the accuracy of daily evapotranspiration data from SEBAL algorithm and some empirical ET equations compared with measured data from a lysimeter in Nezamabad Hashtgerd plain, Alborz province, Iran. For this purpose, the LANDSAT 7 satellite imagery acquired in October 2012 was utilized. Results revealed that ET difference between SEBAL algorithm, and measured values from lysimeter, is 21%. Also, among empirical methods, the results of the Hargreaves equation, was most consistent with the results of the SEBAL algorithm.