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ZnYbTe and CdYbTe thin films were grown by molecular beam epitaxy (MBE) on ZnTe and CdTe buffer layers crystallized on GaAs(100) substrates. At the chosen growth temperature (320°C for CdYbTe and 340°C for ZnYbTe) the maximum concentration of ytterbium was found to be 5% in CdTe and 3% in ZnTe. The layers were characterized by X-ray diffraction, photoluminescence (PL) and reflectivity measurements. X-ray investigations have shown that there was a small admixture of pure YbTe in the samples. From the optical measurements it follows that in CdYbTe and ZnYbTe, Yb can be found both in 2+ (as in YbTe) and 3+ (as in Yb doped II–VI compounds) valence state. The relatively broad PL spectra detected at the energies close to the Yb 3+ 4 f 13 ( 2 F 5 2 → 2 F 7 2 ) transitions indicate that at such a high concentration Yb incorporates with certain inhomogeneity into the crystal lattices of ZnTe and CdTe.