The finite volume method is used to solve 3D Reynolds average N-S equation by RNG k-εturbulence model. Flow phenomena in nozzle using secondary flow thrust vector control technology with the change of the jet flow angle are numerically simulated. The result indicates that the vector angle of thrust is maximal with the injection flow plumbing at the wall. The angle of injection flow has a significant effect on the thrust vector angle, and the reversed jet flow can produce greater thrust vector angle and thrust loss than the parallel jet flow.