Different methods of electrolytic separation of non-metallic inclusions in low carbon steels have been investigated, and certain suggestions for improvement in this connection are proposed.It is shown that for the separation of stable inclusions the more satisfactory procedure is to separate the inclusions and the carbides by the ferrous-sulfate method followed by the dissolution of the carbides either by ammonium-persulfide method or by nitric-acid method, whereas for the separation of unstable inclusions, the sodium-sulfite method gives better results.The modified method supplemented by microscopic examinations has been applied to the study of inclusions in a certain kind of constructional steel with favourable results.