Abstract: The present invention relates to a steel material containing, in terms of mass %: 0.30%?C?0.45%, 0.10%?Si?1.00%, 0.60%?Mn?1.20%, 0.20%?Cr?0.70%, 0.30%?V?0.47%, Ti?0.015%, P?0.100%, and S?0.080%, with the balance being Fe and inevitable impurities, and has a P0 value defined by P0=P0?×V/P1, satisfying P0?0.30, here, P0?=Mn+0.49Cu+0.89Ni+0.40Cr?0.30Si, and P1=C+0.07Si+0.16Mn+0.61P+0.19Cu+0.17Ni+0.2Cr+V, in the formulae, each element symbol indicates a content of each element in units of mass %.