Thin epitaxial layers of Pb1−xSnxTe are grown on (100) KCl substrates by molecular beam epitaxy (MBE) using a single Knudsen source. A typical source temperature of 600 °C and substrate temperatures of 250 to 350 °C are used. Laue, X‐ray, RHEED, SEM, and Van der Pauw techniques are employed to characterize these films. Layers 4 to 5 μm thick are grown at a growth rate of 0.75 μm/h. These layers are found to be p‐type having carrier concentrations in the range of 1017 to 1018 cm−3 and mobilities of the order of 103 cm2/Vs at 110 K. The composition x in the films is found to vary with the substrate temperature and the films grown at 325 °C exhibit the same value of x as the source material. Copyright © 1988 WILEY‐VCH Verlag GmbH & Co. KGaA