Reverse osmosis (RO) is proved to be the most reliable, cost effective, and energy efficient in producing fresh water compared to other desalination technologies. It is the fastest-growing desalination technology with a greater number of installations around the world. The economic and technical performance of a medium-capacity RO desalination plant (2,000 m 3 /day) proposed to be installed in Umm Qasr city south of Basra, Iraq is analyzed using DEEP-3.2 software created by the International Atomic Energy Agency (IAEA). This port city is located on the Gulf shore and does not have any fresh water resources. The analysis shows that the cost of fresh water produced by this plant is US$0.986/m 3 with a good quality of fresh water (279 ppm), which is a reasonable price for this remote area. The analysis also shows an increase in water production cost of about 12% at increased electricity price from 0.06 to 0.1 US$/kWh, 5.3% when the seawater salinity increased from 35,000 to 45,000 ppm, 2.5% when the seawater temperature decreased from 33 o C to 20 o C, and 0.71% when the interest rate increased from 0% to 5%. Pumping fresh water from the Basra purification plant (located 175 km north of Umm Qasr) is 22.16 times the cost and 236.7% poorer quality than the fresh water produced by the RO plant.