Water pollution harms the human and marine environment.  An optimal water quality is a global target for the well-being of all living organisms including human. Based on this concept, tThis study focused on the synthesis of magnetite nanoparticles using the wet chemical reduction technique and their incorporation with the preparation ofing magnetic chitosan hydrogel (CS-HG) nanocomposite. Fourier transform infrared spectroscopy (FT-IR), zeta potential, x-ray diffraction (XRD), x-ray fluorescence (XRF), sScanning electron microscopy (SEM) and energy dispersive X-ray(EDX) were used as the main characterization tools. The magnetic CS-HG was applied to different types of multi-pollutant water to test its efficiency in removing different pollutants. Magnetic hydrogel showed high efficiencies (99.17, 98.27, 95.17, 93.9 and 49.59%) towards removing iron, phosphates, nitrite, nitrate and ammonia/ammonium, respectively. This study also investigated the effectiveness of a chemical treatment process by magnetic CS-HG in reducing bacterial populations in a water sample. The initial bacterial count of tTotal cColiforms (TC) ranged from 600,000 to 5,500,000 CFU/ mL, significantly decreasing to 4,000 to 60,000 CFU/ mL after treatment. Similarly, Pseudomonas counts were reduced from 0 to 25,000 CFU/mL to 50 to 75 CFU/ mL. Notably, Aeromonas sp.and Vibrio sp. were not detected in the samples before or after treatment. Further analysis revealed that some previously identified Pseudomonas isolates belonged to different bacterial genera, including Neobacillus novalis, Psychrobacillus lasiicapitis, Acinetobacter schindleri, and Bacillus paramycoides. Thus,mMagnetic CS-HG could be applied to clean up different kinds of water.