For the first time a comparative study of rhombohedral LaNiO 3 and LaCuO 3 oxides, using 57 Fe Mo¨ssbauer probe spectroscopy (1% atomic rate), has been carried out. In spite of the fact that both oxides are characterized by similar crystal structure and metallic properties, the behavior of 57 Fe probe atoms in such lattices appears essentially different. In the case of LaNi 0.99 Fe 0.01 O 3 , the observed isomer shift (d) value corresponds to Fe 3+ (3d 5 ) cations in high-spin state located in an oxygen octahedral surrounding. In contrast, for the LaCu 0.99 Fe 0.01 O 3 , the obtained d value is comparable to that characterizing the formally tetravalent high-spin Fe 4+ (3d 4 ) cations in octahedral coordination within Fe(IV) perovskite-like ferrates. To explain such a difference, an approach based on the qualitative energy diagrams analysis and the calculations within the cluster configuration interaction method have been developed. It was shown that in the case of LaNi 0.99 Fe 0.01 O 3 , electronic state of nickel is dominated by the d 7 configuration corresponding to the formal ionic ''Ni 3+ -O 2À '' state. On the other hand, in the case of LaCu 0.99 Fe 0.01 O 3 a large amount of charge is transferred via Cu-O bonds from the O:2p bands to the Cu:3d orbitals and the ground state is dominated by the d 9 L configuration (''Cu 2+ ÀO'' state). The dominant d 9 L ground state for the (CuO 6 ) sublattice induces in the environment of the 57 Fe probe cations a charge transfer Fe 3+ +O À (L)-Fe 4+ +O 2À , which transforms ''Fe 3+ '' into ''Fe 4+ '' state. The analysis of the isomer shift value for the formally ''Fe 4+ '' ions in perovskite-like oxides clearly proved a drastic influence of the 4s iron orbitals population on the FeÀO bonds character.