Abstract: The jet tab thrust vector control technology discussed in this paper has outstanding advantages in less thrust loss, faster response, stronger control forces, compared with jet vane technology, which meet the needs of future air combat for advanced air-to-air missile. In order to meet the requirements of control rate modeling and optimization of jet tab thrust vector control system, conical nozzle with spoilers in three different shapes, which are round, rectangle and sector, are numerically simulated. The effects of spoiler geometry parameters on the thrust vector performance are analyzed. The design method of reducing thrust loss of spoiler is presented. The results indicate that thrust vector angle and thrust loss ratio increases with increasing insertion depth of the spoiler. For the rectangular spoiler, thrust loss ratio decreases with the increase of spoiler width; and for the sector spoiler, thrust loss ratio decreases with the increase of the design parameter l. When the spoiler inserted depth and inserted area is constant, rectangle spoiler has the maximum thrust vector angle and thrust loss ratio, while round spoiler has the minimum.