The kinetics of the bainitic transformation near the Ms temperature was studied in chromium - nickel - molybdenum steels with different silicon contents. The kinetics of this transformation was found to be the same irrespective of whether it occurs above or below the Ms temperature, and be satisfactorily described by the Avrami equation. The austenite grain refinement increases the stability of the overcooled austenite in the region of the bainitic transformation.