Sodium silicate glasses with a constant ratio of oxide concentrations (mol %) SiO₂/Na₂O = 2.4 and with copper ions introduced in the form of CuO (from 1 to 10 mol %) are studied by the EPR method. The shape and width of the EPR line of copper ions are analyzed, and the spin-Hamiltonian parameters g _||, g _⊥, A _||, and A _⊥ are determined by simulating the EPR spectrum and comparing the simulated and experimental spectra. The EPR spectrum of copper ions (1 mol %) is characterized by the parameters g _|| = 2.35, g _⊥ = 2.065, A _|| = 135 × 10^–4 cm^–1, A _⊥ = 7 × 10^–4 cm^–1, and ΔH = 25 G. An analysis of this spectrum shows that the nearest environment of the Cu²⁺ ion has the shape of an elongated octahedron. The EPR spectrum of the sodium silicate glass containing 10 mol % Cu is a superposition of the spectrum of an octahedral complex (g _|| = 2.35, g _⊥ = 2.075, A _|| = 135 × 10^–4 cm^–1, ΔH = 40 G) and the spectrum of a cluster (g _|| = 2.35, g _⊥ = 2.15, A _|| = 135 × 10^–4 cm^–1, ΔH = 50 G).