Gd(Fe,Mn)O3 nanoperovskites were prepared by sol-gel method and were characterized using different techniques: XRD, SEM+EDX, BET, TG to study structure and morphology. Oxidation states of Fe and Mn were determined by XPS. The performance of GdFe1-xMnxO3 perovskite catalysts with different Mn substitution levels was evaluated in the CO hydrogenаtion for light olefins production. The complex of physico-chemical methods showed that all investigated samples confirmed the presence of a single phase with perovskite-type structure. Experimental data suggested that catalysts can operate over a wide temperature range without any loss of activity and are practically unaffected by surface carbonation; their phase composition and morphology of the surface change insignificantly in catalytic processes at high temperature (~ 673 K). It was determined that the introduction of manganese into perovskite structure led to a change in the quantitative composition: the amount of butylene was much higher than that of ethylene on the samples containing manganese in the B-site. Activation of catalytic centers and their further stabilization taking place under the action of the reaction medium was established for all the systems studied. © 2019 Bulgarian Academy of Sciences, Union of Chemists in Bulgaria.