Thermal power plants are the major type of power plants in Egypt. The percentage between the thermal electrical power plants to hydropower plants in Egypt is 3: 1. About 93% of industrial water are used for cooling or condensing purposes, while less than 2% are used as boiler feed water. The discharge of heated wastewater from electricity generating stations causes thermal pollution, which adversely affects the receiving water bodies. Thus, the aim of this work was to investigate any thermal impact resulted from both Abu-Qir and El-Seiouf steam power plants outlet cooling systems. The results revealed that the temperature values of cooling system outlet units 1, 2, 3, 4 and 5 of Abu Qir power plant are within acceptable limits [mean value of 35.6°C]. Physical and chemical parameters of Abu Qir effluent cooling wastewater indicated accepted limits as well, e.g., suspended solids, dissolved oxygen, BOD, COD and oil and grease [mean values are 28.5-7.6-14.65-27.83-13.33 mg/l respectively]. On the other hand, El-Seiouf power plant cooling system outlet units showed a relative increase in temperature than the accepted limits of environmental law 48/82 of fresh water [mean value is 40.8°C while maximum accepted value of environmental low for fresh water is 35°C] which may cause thermal pollution to El-Mahmoudia canal. Some of the measured parameters of El-Seiouf outlet cooling hot channel were higher than the accepted limits e.g., suspended solids, BOD, COD, oil and greese and phosphates [mean values are 67.5-67-111.83-66 and 2.11mg/l respectively while maximujm values of environmental low for fresh water are 30-30-40-5 and 1mg/l respectively]. The study recommends the renovation of El-Seiouf power plant cooling system to avoid thermal pollution of El-Mahmoudia canal and/or the use of chlorine injection in the cooling Lower inlet to improve effluent wastewater quality. The implementation of using sea water in cooling systems in future power plants on coastal areas, is also, recommended such as Sidi-Kirer power plant.