Energy requirements in desalination plants can be supplied by coupling desalination units with nuclear reactors. Multistage flash (MSF) plants often use low-pressure steam as an energy source. The energy consumption in MSF plant depends on the distillate flow rate and the plant performance ratio. Reverse osmosis (RO) plants are operated by electrical power to derive the high-pressure pumps and other plant auxiliaries, mainly the pretreatment processes. RO power consumption depends mainly on water recovery and the working pressure. Low pressure and temperature steam extracted from nuclear heating reactors (NHR) may be used for supplying the necessary energy to derive the MSF units. Electricity can be generated from the nuclear power reactor (NPR) to derive the high-pressure pumps of the RO desalination plants. Coupling RO and MSF with nuclear steam supply system (NSSS) will yield some economical and technical advantages. The hybrid RO MSF system has potential advantages of a low power demand, improved water quality and possible lower running cost as compared to stand-alone RO or MSF plants. Developing the most appropriate plant configuration of nuclear reactor and desalination process is an important task that will determine the feasibility of nuclear desalination. The optimum coupling of hybrid RO MSF desalination processes with nuclear power plant will be presented in this paper.