Fe3O4 nanoparticles coated with humic acids isolated from chernozem, sapropel, peat and brown coal were obtained using hydrothermal synthesis. The properties of the obtained sorbents were carried out using IR spectroscopy, SEM and TEM, whereas saturation magnetization was established using a vibration magnetometer. The maximum content of nitrogen-containing groups was found in humic acids obtained from sapropel, while the minimum amount was found in brown coal. The sorption properties of these polymers were checked among 12 different phenols. It was found that the maximum efficiency of sorption was achieved at pH of 3–4. The extraction degree is maximum for the nanoparticle sample coated with sapropel and equals 61, 65, 65, 71, 79, 89, 68, 67, 64, 62, 60, 94 for phenol, 2-chlorophenol, 4-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol, pentachlorophenol, 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol, 2,4,6- trinitrophenol, guaiacol and nonylphenol respectively (the sorbent mass being 0.05 g and the solution volume being 10 cm3). The sorption equilibrium for the most hydrophilic phenols is achieved in 30 minutes, whereas for hydrophobic phenols it is about 60 minutes. The maximum sorption of the studied compounds on the most efficient sorbent (Fe3O4@СП) varies from 112 mg/g (for phenol) to 466 mg/g (for pentachlorophenol).