In the research, a one-step method for the rapid preparation of spherical nanostructured particles of Ca3Co4O9, involving the combustion of reactive aerosol drops containing calcium and cobalt nitrates as the metal precursors and hexamethylenetetramine as the fuel, is reported. The results of thermodynamic analysis and study of crystalline structure of obtained materials suggest that the reaction in the investigated system proceeds with heat release, which indicates its self-sustaining nature. Applying hexamethylenetetramine fuel at φ range of 0.4 – 0.6 and ambient temperature of 900 ℃ resulted in formation of Ca3Co4O9 powders with narrow particle size distribution of 0.2 – 1 µm. Microstructural studies revealed that the Ca3Co4O9 particles are hollow with nanometer-scale wall thicknesses and their surface consists of lamellar grains with sizes ranging from 14 to 100 nm.