Abstract: An optimum design of the dive trajectory for a cruise missile is presented.The dive process is analyzed, based on which the optimization problem is modeled as the minimization of discrepancy between the required parameters of penetration and the parameters at the end of the dive maneuver subjected to the overload and engine performance constraints.Genetic algorithm is applied to solve this optimization problem.To reduce the amount of computation, non-uniform rational B-spline(NRUBS) curve is utilized to represent the complex laws of flight control. A simulation example is provided in the last section and its results are analyzed in detail.