Abstract: A model based on the characteristic maps of the variable geometric components is applied to performance estimation of Variable Geometry turborfan Engine (VGE).The influences of readjusting the geometric parameters,such as the variable guide vanes of fan and compressor,and variable turbine throat areas,on the installed and uninstalled performance have been researched for a VGE with high thrust-weight ratio.The results show that a significant influence on the engine performance is exerted by shifting the fan variable vanes,but a less influence by adjusting the other three parameters under the calculation conditions selected.But if the four parameters could be readjusted coordinatively,the components will be controlled with high efficiency to ensure the high performance of VGE.