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Evapotranspiration (ET), which is the sum of plant transpiration and soil evaporation, is a continuous process of water loss in the soil-plant-atmosphere continuum. An accurate prediction of ET is necessary for developing agricultural management strategies to improve water use efficiency and ensure sustainable agricultural production, especially for regions subjected to water scarcity. This study used the dual-source Shuttleworth-Wallace (SW) model to quantify the subsequent components of ET (transpiration and evaporation) in jujube (Ziziphus jujuba Mill.) plantations in the fragile, semi-arid, hilly Loess Plateau region of Mengcha Village in Shaanxi Province, China. Thermal Diffuse Probe (TDP) measuring transpiration and estimated evapotranspiration (ET) via local water balance method were used to validate the SW-model estimations for the 2012 jujube growth seasons. The estimated precision of the hourly and daily transpiration varied with weather conditions and the accuracy of ET depended on the growth stage. However, the estimated transpiration and ET were within acceptable values. During the growth seasons, jujube forest consumed some 463 mm (approximate to 103%) of the annual precipitation (451 mm), approximate to 65% of which is transpiration and 35% evaporation. This corresponds to a significant water stress under the rain-fed cultivated jujube plant in the study area. Nighttime transpiration was small and approximate to 81% of the total transpiration occurred in the daytime. This study further verified the suitability of the SW-model application in semiarid, rain-fed conditions and is useful for managing local jujube water consumption. (C) 2013 Friends Science Publishers