The most common method for seawater desalination is based on the reverse osmosis (RO) process. RO membranes separate all the dissolved salts and produce potable water. The aim of this project is to produce a high-flux RO membrane for seawater desalination. Three membranes are cast with 2%, 2.5%, and 3% of graphene oxide and titanium dioxide nanoparticles, respectively. Seawater is passed through the membrane with a high-pressure water gun. The outlet water is analyzed for flux, pH, electrical conductivity (EC), and total hardness (TH). The highest flux, that of 3571 L/m−2/h−1, is achieved with a membrane made up of 3% graphene oxide and titanium dioxide nanoparticles. The correlation coefficient (CC) between average conductivity and total hardness values is calculated, yielding 0.968. The fouling on membranes was studied with scanning electron microscope (SEM) images, which was reduced by increasing the nanoparticle concentration.