Synthesis of the xCuO–(1−x)Bi 2 O 3 (0.5⩽x⩽0.9) (C1–C5: x=0.5, 0.6, 0.7, 0.8, 0.9) glasses was done via nitrate–citrate gel route. Glassy phase is ascertained by XRD studies. Magnetic susceptibility results in the range 4.2–400K show weak paramagnetic nature with exchange integrals ∼0.024–0.13eV in the glasses. The electron paramagnetic resonance (EPR) in the range 4.2–363K shows g≈2.0 and the trend of the g-matrix elements g || >g ⊥ >g e for the glasses C1–C5 at 4.2K are due to the Cu 2+ (3d 9 ) paramagnetic site in the glasses which is in a tetragonally elongated octahedron [O 1/2 –CuO 4/2 –O 1/2 ] having D 4h symmetry. IR spectroscopic results show the presence of octahedron [BiO 6/2 ] 3− and [CuO 6/2 ] 4− units and pyramidal [BiO 2/2 O] − unit in the glasses.