The Mid-Yellow River region has been facing serious problems such as the most extensive soil erosion and water loss in the world, water shortage, flood disasters, ecological and environmental degradation. Evapotranspiration is a key component in the energy and water balance and plays an important role in the water cycle of the Mid-Yellow River region. Study on evapotranspiration and water consumption of vegetation (including forests and grasslands) over the Mid-Yellow River region will give basic knowledge of water supply and demand as well as water-consuming characteristics of vegetation. This study will also contribute to rationally develop and use limited water resources in the Mid-Yellow River region, and therefore, it has theoretical and practical significance. In this paper, based on Remote Sensing and GIS techniques, evapotranspiration and water consumption by vegetation were estimated in the Mid-Yellow River region. First, after the geometric correction, radiometric calibration and false color composition, Landsat TM Remote Sensing image in 2000 were interpreted carefully and the vegetation distribution data in the Mid-Yellow River region were gained. Then, by the ArcGIS 8.3 Software, the total area of various vegetation types was figured out and the 1km-Grid dataset was established by which the proportions and ratios of every type of vegetation on the scale of one square kilometer have been expressed. Finally, based on the meteorological data and the Penman-Monteith Method, evapotranspiration and water consumption for various types of vegetation were estimated. The results showed that in the Mid-Yellow River region, water consumption by forests and grasslands were 31.41 billion m3 and 44.08 billion m3 respectively.