The present invention relates to a steel for a mold including: on % by mass basis, 0.55%≤C≤0.70%; 0.30%≤Si≤0.60%; 0.55%≤Mn≤1.2%; 5.7%≤Cr≤6.9%; 1.2%≤Mo+W/2≤1.6%; 0.55%≤V≤0.79%; and 0.005%≤N≤0.1%, with the remainder being Fe and inevitable impurities including, Al≤0.020%, Ni≤0.20%, S≤0.0015%, and Cu≤0.10%, and satisfying P1≥24 and 4.9≤P2≤7.3, P1 and P2 being a value obtained based on the following formula (1) and (2), respectively, P1=45−13.6[Si]−7.0([Mo]+[W]/2)−12.9[Ni] (1), P2=7.4[V]+15.8[N]+38.6[Al] (2) in which [M] represents a content of an element M in % by mass basis, and relates to a mold including the steel for a mold.