Pollution of water resources as a result of the discharge of industrial wastewater containing heavy metal ions is a serious problem in world practice. New ion exchange sorbents make it possible to solve two related problems at once: purification of industrial water from enterprises and regulation of the content of toxicants in the environment. This study is focused on the synthesis and use of modified glycidyl methacrylate copolymers as an adsorbent, providing the greatest selectivity among the heavy metal ions required for effective adsorption. A comprehensive characterization and analysis of ion exchanger GMA-ACN-PEI (glycidyl methacrylate-acrylonitrile-polyethylenimine) was carried out using Fourier transform infrared spectroscopy (FTIR), determination of chemical stability, thermogravimetric analysis (TGA). Efficiency of sorption-selective abilities towards Cu (II) and Pb (II) ions were assessed using atomic adsorption spectroscopy methods. Removal efficiency was obtained to be 85.6% and 77.8% for Pb (II) and Cu (II) ions respectively. To assess the influence of various factors on the adsorption process, periodic experiments were carried out, varying parameters such as temperature and curing time. Langmuir adsorption isotherm was found to be the best model to describe the effectiveness of the synthesized copolymer.