Energy conservation and energy management, which is important thing that must be done by industrial players in Indonesia, has a purpose for optimizing energy usage. it becomes important in electricity, because rising of the electricity cost makes electricity itself not being a cheap thing anymore. For decreasing the electricity cost that should be paid, it is necessary to do energy conservation on electrical energy. Electric motor is one of the core parts of industrial sector that has the biggest electricity consumption. In other words, if the energy conservation needs to be done in industrial area, so that means it can be focused in electric motors. In that case of pressing electricity cost, suitable strategy can be reached by not only considering to the technical aspect but also economical aspect. Life cycle cost and payback period are some of the economic assessment tools which can be helped for assesing strategy in many cases. By using those tools, it can be reached the assessment of replacing strategy that is used in induction motors in salt industry, which is used as a one of the tools to make a decision. This paper will explain about how to use life cycle cost and payback period in induction motors replacement case.