Provided are a high-strength steel sheet having high strength of a yield strength of 550 MPa or more and a method for manufacturing the same.
The high-strength steel sheet has a specified chemical composition and a microstructure, where observed in a cross section in a thickness direction perpendicular to a rolling direction, including a martensite phase having a volume fraction of 50% to 80%, and a ferrite phase having an average grain diameter of 13 μm or less, wherein a volume fraction of ferrite grains having an aspect ratio of 2.0 or less with respect to the whole ferrite phase is 70% or more, and wherein an average length in a longitudinal direction (in a width direction of the steel sheet) of the ferrite grains is 20 μm or less, and a yield strength (YP) of 550 MPa or more.