This study used the weighted mathematical model to assess the quality of water produced from the desalination station of Hawija district from 3 sites of the raw water source and 7 sites from the treatment station and the distribution network). The study was conducted from November 2021 to April 2022. The first group of the plantations or cites includes feeding streams which are cites 1 and 2. The 7 sites were divided into two groups. The second group included the sites inside the station which were 3, 4, and 5. The values of the water quality coefficient varied in relation to the stages of water desalination. These values in cites 3 and 4 were poor because they reflected the beginning of the treatment stages of the water in the treatment plant, while the water quality factor in site 5 became excellent indicating the beginning of the stages of water treatment in this site. The third group which included cites 6, 7 and 9 represented the distribution grid in the district where the water quality was excellent. As for site 8, the water quality factor was good, and this site was the Al-Nida neighborhood in the distribution grid.