Abstract: In order to avoid cross couplings between the vertical and lateral motion,decoupling control of a double-channel control rolling missile autopilot was studied.Such couplings in autopilot loop are analyzed.Couplings of motion,control and the accelerometer placed a distance ahead of the c.g.exist in the rolling missile autopilot loop.Test results showed that the autopilot design needs decoupling.Trajectory simulation was conducted for a certain kind of missile controlled under optimization command.Simulation results proved that the scheme was feasible and had perfect application value.