The features of the formation of nanocrystals in the BiFeO₃–CaFeO₃ system via glycine-nitrate combustion were studied. The crystallite size of the bismuth orthoferrite-based solid solutions (20–45 nm), as well as their particle size, were found to depend on the calcium content. The formation processes were activated in the temperature range corresponding to the melting of the surface (nonautonomous) phase.