Abstract: A mathematical model of turbofan engine with thrust vector control was established.By employing certain turbofan engine as a sample,the effects of vector thrust control on turbofan engine performance and co-operation were studied.Under certain conditions,the results show that the operation line of low-pressure spool moves towards the surge margin when the thrust vector nozzle deflected.But the operation line of high-pressure spool does not change,and the total thrust increases.When combining deflection of the thrust vector nozzle with increasing the nozzle area,the original operation situation of the turbofan engine can be kept.But the total thrust of the turbofan engine is decreased.