The principle of the method specified is dissolving a test portion in hydrochloric and nitric acids followed by evaporation with perchloric acid until white fumes appear, spraying the solution into an air-acetylene flame, spectrometrically measuring the atomic absorption of the 279,5 nm spectral line emitted by a manganese hollow cathode lamp. The method is applicable to manganese contents between 0,002 % (m/m) and 2,0 % (m/m).