We present results of measurements of temperature dependence of the magnetic susceptibility and soft X-absorption spectra of double-substitution solid solutions Sr1-xCexMn1-yCoyO3-delta. It was found that in the solid solution Sr0.8Ce0.2Co0.2Mn0.8O2.96, cobalt and cerium ions are in the Co2+ and Ce4+ valence states, respectively. About 90% of manganese ions in Sr0.8Ce0.2Co0.2Mn0.8O2.96 are in the 4+ state, and the rest of them are in the 3+ state. In the solid solution Sr0.9Ce0.1Co0.4Mn0.6O2.85, manganese and cerium ions are in the 4+ states. About 75% of cobalt ions are in the high-spin Co3+ state and 25% of cobalt ions are in the 2+ state. Doping Mn position with Co ions reduces the antiferromagnetic interaction in the initial compounds, which leads to a decrease of the Neel temperature and to the magnetic transition of the material into the spin-glass state. (C) 2016 Elsevier B.V. All rights reserved.