Abstract: During the great depression of iron industry at present,a united enterprise of mining- dressing-smelting should do meticulous planning and careful accounting to get more profits.The research on the optimization of technological indexes is one of good ways.Rules of optimization include integration,dynamics and multi-objects.Integration means the maximum profit is assessed from the whole enterprise,but not from a single department;Dynamics indicates that some mathematical models of geology,mining,dressing and smelting are set up.There exist several objects to be made,so it is necessary to apply fuzzy-comprehensive-evaluation to choose the best technological indexes from many plans.