The invention relates to a heavy-gauge hydrogen steel plate and its production method. The steel plate comprises the following chemical components, by weight, 0.17% or less of C, 0.44-0.86% of Si, 0.35-0.73% of Mn, 0.010% or less of P, 0.009% or less of S, 0.30% or less of Ni, 0.94-1.56% of Cr, 0.20% or less of Cu, 0.40-0.70% of Mo, 0.003% or less of Sb, 0.010% or less of Sn, 0.012% or less of As, 0.0002% or less of H, 0.020-0.045% of Tal, and the balance Fe and inevitable impurities. The steel plate has following advantages: 1, the strength and toughness coupling is good, the yield strength Re is equal to or greater than 310Mpa, and the transverse Charpy impact energy at the 1/2 thickness position of the plate at -18DEG C is not less than 54J; 2, the steel is pure, the P content is equal to or less than 0.08%, and the S content is equal to or less than 0.004; 3, the layered tearing resistance is good, and the through thickness direction Z is equal to or greater than 35%; 4, the welding performance is good; and 5, the thickness of the steel plate reaches 162mm. Test results show that the steel plate produced through adopting the method of the invention has the characteristics of high purity, uniform components and compact inside, has a high steel metallurgy level, and has mechanical performances which can completely satisfy standard requirements of American ASME. The C component is equivalently designed, so the good strength and toughness coupling is possessed.