The vacuum solar receiver is the key component of a parabolic trough solar plant which plays a prominent role in the gross system efficiency Recently China's first high temperature vacuum receiver Sanle-3 HCE has been developed and produced by Southeast University and Sanle Electronic Group Before being utilized in China's first parabolic trough solar plant, accurately estimating the thermal properties of this new receiver is important This paper first establishes and optimizes a 1-D theoretical model at Matlab program to compute the receiver's major heat loss through glass envelope and then systematically analyzes the major influence factors of heat loss With the laboratorial steady state test stand, the heat losses of both good vacuum and non-vacuum Sanle-3 receivers were surveyed Comparison shows the original 1-D model agrees with the ends covered test while remarkably deviating from end exposed test For the purpose of identifying the influence of receiver's end to total heat loss, an additional 3 D model is built by CFD software to further investigate the different heat transfer processes of receiver's end components The 3-D end model is verified by heating power and IR temperature distribution images in the test Combining the optimized 1-D model with the new 3-D end model, the comparison with test data shows a good accordance At the same time the heat loss curve and emittance curve of this new receiver are given and compared with those of several other existing receivers as references (C) 2010 Elsevier Ltd All rights reserved