The invention discloses E40 high-strength ship plate steel. The E40 high-strength ship plate steel comprises, by
mass, from 0.13% to 0.16% of C, from 0.2% to 0.4% of Si, from 1.5% to 1.6% of Mn, lower than or equal to 0.03% of P, lower than or equal to 0.005% of S, from 0.30% to 0.35% of Ni, from 0.055% to 0.065% of V, from 0.035% to 0.045% of Nb, from 0.010% to 0.020% of Ti, from 0.015% to 0.035% of Als and the balance Fe. A method for manufacturing the E40 high-strength ship plate steel includes a pretreatment process for melted iron, a
smelting process implemented by the aid of a converter, an
argon blowing treatment process, an LF (
ladle furnace) refining process, a VD (vacuum
degasser) refining process, a
continuous casting process, a heating process, a controlled rolling and controlled cooling process, a stack cooling process and a heat treatment process. The E40 high-strength ship plate steel and the method have the advantages that the E40 high-strength steel is successfully developed, the yield strength of the E40 high-strength ship plate steel ranges from 430MPa to 450MPa, the tensile strength of the E40 high-strength ship plate steel ranges from 550MPa to 580MPa, the elongation of the E40 high-strength ship plate steel ranges from 22% to 24%, V-type
impact power of the E40 high-strength ship plate steel ranges from 210J to 280J at the temperature of minus 40 DEG C, and performance indexes of a steel plate made of the E40 high-strength ship plate steel completely meet standards and requirements of clients.