Abstarct: One of the ways to recover heat waste in industries is to use cogeneration systems to produce power, heating and fresh water. In this research, by using the investigations carried out in the processes of Shahrood Steel Factory, the potential of waste heat recovery in order to produce power and also to provide energy for desalination plant of the factory has been investigated. The reduction phase in this factory is in the design phase by an external consultant, and the melting and rolling phases are in operation. Therefore, using the design data of the external contractor of the reduction phase and also the measurement of the parameters of the exhaust gas of the preheated rolling furnace, a technical and economic study has been carried out to recover the waste of the furnaces. According to the temperature and mass flow rate of the exhaust gases from the stacks and the calculations and modeling in EES software, it was determined that the Organic Rankine Cycle (ORC) is capable of producing 120.6 kW power in the rolling phase and the Steam Rankine Cycle (SRC) has the ability to produce 8576 kW of power in the reduction phase. According to the amount of water required by the factory, the suitable RO desalination plant has been determined by ROSA software and its technical parameters such as electricity consumption are presented. By estimation of investment costs, operation and maintenance cost and income of the cycles, economic analysis of each cycle separately, as well as two cycles together, is performed. Also effect of interest rates on return on investment of various senarios is determined. From environmental point of view, the release of 68868 tons of carbon dioxide into the environment per year is prevented and water consumption can be reduced by 500 cubic meters per day.