Abstarct: Waste heat recovery plays an important role in energy resource management. Low grade waste heat could be recovered by Organic Rankine Cycle (ORC). This is the same as the Rankine cycle and an organic fluid is used as working fluid. in the present study energy and exergy analysis was performed to improve the performance cycle, Thus effects of various parameters were evaluated such as: the effects of using different pure working fluids, the effects of using two-component mixtures with different temperature glides during phase change, effects of superheated steam inlet to the turbine, effect of the internal heat exchanger, effects of temperature difference between the heat source input and output. Due to considering constant inlet and outlet temperatures of heat source heat carrier fluid and its mass flow rate, reasonable comparison was performed in evaluate the effects of various parameters on performance of cycle, thus improvement factors of the performance cycle was achieved. These factors will lead to increased efficiency: If the temperature difference between the inlet and outlet of the heat source is low, using the internal heat exchanger is appropriate otherwise is inappropriate. Approximately can be said, if the temperature difference between the inlet and outlet of the heat source is low and the internal heat exchanger is used, superheated steam inlet the turbine is appropriate, otherwise is inappropriate. If the temperature difference between the inlet and outlet of the heat source is low, using the working fluid with a higher critical temperature leads to increase of efficiency, and if the temperature difference between the inlet and outlet of the heat source is high, using the working fluid with a lower critical temperature is more appropriate. Using the mixture working fluids in comparison with pure fluids leads to increase of efficiency, of course the effect is less if the temperature difference between the inlet and outlet of the heat source is low and the effect is more if the temperature difference between the inlet and outlet of the heat source is high. If the temperature difference between the inlet and outlet of the heat source is low, using the mixture working fluids in configuration with internal heat exchanger leads to better efficiency in comparison with using mixture fluids in simple configuration, this is contrary if the temperature difference between the inlet and outlet of the heat source is high. Whenever the used mixture working fluid simultaneously have the best match with hot and cold flow in vaporizer and evaporator, best efficiency is achieved.