For dealing with cost control problems of material substitution in steel production process in make-to-order
steel enterprise, we established the substitution rules of material substitution and built up the cost optimized controlling
model for material substitution. The objective function of this model was to minimize the total cost of both stock and task
lateness. We made use of Operations Research and Genetic Algorithm to solve this model. Finally, we also conducted the
application research for the model and algorithm, and its promising future was revealed.