Abstract: Large reflector antennas are deformed under various structural loads, which will deteriorate their electromagnetic performance. Electro-mechanical analysis is often used to predict the impact of loads on electromagnetic performance. To deal with the problems of low analysis efficiency and poor effect caused by heterogeneous models, trivial grid conversion process and loss of geometric accuracy in traditional electromechanical coupling methods, in this paper, an electromechanical coupling analysis framework was proposed based on non-uniform rational B-splines (NURBS) for geometric modeling, structural and electromagnetic analysis, and the convenience and efficiency of this method were proved by cases. This framework provides a powerful tool for radiation pattern analysis of mechanically distorted reflector antennas and antenna tolerance research.