Abstract: A new optimization method applied to the engineering design called as rotate-vector method is put forward which is proper to solve the nonlinear plan problem with restraints. Through making use of the vector's rotating around the low terminate point and contracting, the vector is converging step by step, and the optimization point can be obtain at last. With great deal of examples being worked out, the new method has proved valid, available and general purpose.

Key words: Computational methods, Optimization methods, Rotate-vector