PURPOSE: To combinedly improve the workability and hardenability of the steel for rolling parts by reducing the contents of Mn and Si, adding Cr and Mo so as to compensate the hardenability and specifying the compsn.

CONSTITUTION: The steel for rolling parts is constituted of, by weight, 0.1 to 0.7% C, ≤0.04% Si, ≤0.25% Mn, 0.2 to 1.0% Cr, ≤0.8% Mo, ≤0.01% P, ≤0.003% S, ≤0.0015% O and the balance Fe. In the steel, since S and O form inclusions deteriorating the deformability at the time of plastic working, each is regulated to the upper limit or below. Since Mn and Si increase the deformation resistance and deteriorate the plastic workability as well as Mn forms MnS with S as impurities and causes the generation of cracks, each is regulated to the upper limit or below. Then, the deterioration of the hardenability caused by the reduction of the contents of Mn and Si is compensated by the addition of Cr and Mo.