Abstract The EPR spectra of Gd 3+ and Eu 2+ in the lead chalcogenides PbS, PbSe and PbTe have been studied at room temperature. In each case the fine structure is characteristic of cubic field splitting. The b 4 values for the europium doped samples show a steady decrease in going from PbS to PbTe, but the b 4 values for the gadolinium doped materials are approximately constant. These results are interpreted in terms of a simple electrostatic model. The Eu 2+ ions are assumed to occupy a lattice site, and the Gd 3+ ions an interstitial site around which distortion of the lattice has taken place.