In this thesis, the cost of products and services utilizing Activity Based Costing(ABC) method is determined and implementated in oxygen unit of Hormozgan Steel Company. ABC is one of the systems for determining the cost of products and services that provides better and more accurate information for experts. One disadvantage of traditional costing system is that the biggest part of costs is considered as overhead costs and therefor distributed equally among the goods of company. This problem can causes incorrect decisions. with, ABC system costs of every activities is identifed and allocated to each goods, or services, and though decreases allocation of costs as overhead costs. To determine the cost of products and services utilizing ABC method and implement it in oxygen unit of Hormozgan steel company, financial statements and information were studied (from 20 th march till 21 st December of 2014). Center of main activities were determined, and then these activities were incorporated logically. Eventually 21 activities were identified serve as base of ABC system. For determination using experts idea, 5 criterias were used to select the best cost drivers. In the next step these criterias utilizing FANP method were weighted and for every activities the best cost drivers were selected utilizing corrected FTOPSIS. Finally according to this information the costs were allocated. In implementation of this system in oxygen unit of Hormozgan steel company, more than 95.7 percent of all the costs were detected. After correction cost of products in oxygen unit, cost of steel products for one year was calculated. The results showed a very significant difference with perivious calculations. The results of this research showed, using ABC system can allocate overhead costs more accurate. Furthermore, ABC helps managers to make better decisions and helps company to achieve more benefits.
