The RE (RE=La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, and Dy) and Mn ions co-doped Co-Zn ferrites were prepared by solid-state reaction method. X-ray diffraction, infrared spectra. X-ray photoelectron spectroscopy. Mossbauer spectroscopy and infrared emission measurement (IRE-2) were employed to investigate the effect of the substitution RE3+ and Mn ions for Fe3+ ones on the spinel structure, the chemical homogeneity, and the infrared emission properties of the Co-Zn ferrites. The substitution leads to non-monotonous change of the lattice parameters and infrared emissivity properties, which is mainly attributed to the partial cation exchange among the spinel structure of Co-Zn ferrites. The infrared emission properties of Co-Zn ferrites seem to be greatly influenced by the co-doped of RE3+ and Mn ions maxima values were 0.96-0.97, found for LaF, NdF and GdF, respectively. (C) 2011 Elsevier B.V. All rights reserved.