A guidance method used in boost phase for intercepting the high-speed target in outer space was presented.After constructing the model of motion of the target and the kinetic kill vehicle(KKV)

constraints of interception were analyzed and the computing method of orbit transfer was also derived.Then orbit transfer was optimized to get valid launching areas satisfying the constraints.Moreover

KKV's required velocity increase at firing time was selected as the specific performance index to optimize the computed launch parameters.Simulation results show that this method can implement efficiently KKV's guidance during the boost phase.