Iron and Steel industry are an industry that requires high accuracy in decision making because of several factors such as the technical impact of the decision, safety factors (Health Safety Environment) and the economic impact from the decision. This paper discusses the operational decision making which are crucial in managing operations of an iron and steel processing plant. The determination of decision is based on experience and expertise that are based on engineering calculations from the supporting engineers. The method used are conducting a qualitative study on two decision making cases by interviewing the senior engineer of several iron and steel companies in Indonesia. Results show that the heuristic approach to decision making are the dominant method and perceived as effective for operational activities that are technical in nature. But whether this method is the best is still questionable. Because thereare other approaches that can gather many experts and can make better technical decisions such as using pairwise comparisons. Limitations of this research are the amount of interviewed persons that does not generalize the real situations in the iron and steel industry in Indonesia. This study will contribute to the studies on operational management in iron and steel industries and provides managerial insights for stakeholders that are in the field of of iron and steel and other similar industries.