Numerical studies were performed to analyze the thrust-vectoring performances of a bypass dual throat nozzle (BDTN) under different conditions. The main results show that：The BDTN has the same flow-filed structure with the conventional dual throat nozzle (DTN), but can generate a better thrust vectoring performance with producing more steady and ef?cient vectoring de?ection. A thrust vector angle of 24.6° is obtained with little thrust penalty. The thrust vector angle and the thrust ratio are decreasing with NPR increasing. The high temperature and high pressure can lead to the thrust vectoring ef?ciency loss tremendously with the thrust vector angle can decrease to 12.75°and the thrust ratio can decrease to 0.882.