Disclosed are a quenched steel sheet and a method for manufacturing the same. The quenched steel sheet according to an aspect of the present invention contains, in terms of wt %, C: 0.05˜0.25%, Si: 0.5% or less (excluding 0), Mn: 0.1˜2.0%, P: 0.05% or less, S: 0.03% or less, the remainder Fe, and other unavoidable impurities, wherein a refined structure of the steel sheet comprises 90 volume % or more of martensite with a first hardness and martensite with a second hardness.