ABSTRACT Thermal power plants are still widely used for electricity production from hydrocarbon sources which are one of electricity generation options. Thermal Power Plants, due to their complex structure, are composed of sections that interact with each other and are called units, and a change in the performance of any unit or equipment affects the operation of the entire plant positively or negatively. Performance monitoring and evaluation systems are designed to support the measurement and monitoring of the performance of staff and equipment and to increase the availability by preparing equipment based maintenance plans according to the maintenance needs of the equipment. KEYWORDS: Electricity generation, Performance monitoring system...