Investigations have been performed for MBE-grown, Pb-doped ZnSe crystal layers on crystallographic as well as PL characteristics. An intense green emission has been observed in ZnSe layers at low temperatures under focused 325 nm wavelength excitation. The green emission was shown to have a nonlinear dependence upon excitation intensity. A correlation between the green emission intensity and Ph flux during the growth has shown that the green emission is related to the presence of Pb atoms, particularly isolated Pb atoms. Excitation intensity and temperature dependence of the green emission has been studied and the mechanism leading to the green emission is discussed. (C) 2003 Elsevier Science B.V. All rights reserved.