A steel plate having excellent hydrogen-induced cracking resistance, comprising, in percent by mass: 0.02 to 0.15% of C; 0.15 to 0.50% of Si; 0.6 to 2.0% of Mn; more than 0% and 0.030% or less of P; more than 0% and 0.003% or less of S; 0.010 to 0.08% of Al; 0.0003 to 0.0060% of Ca; 0.001 to 0.01% of N; more than 0% and 0.0045% or less of O; 0.0002% or more and 0.0047% or less of REM; and 0.0003% or more and 0.010% or less of Zr; and optionally one or more elements selected from the group consisting of: more than 0% and 0.005% or less of B, more than 0% and 0.1% or less of V, more than 0% and 1.5% or less of Cu, more than 0% and 1.5% or less of Ni, more than 0% and 1.5% or less of Cr, more than 0% and 1.5% or less of Mo, and more than 0% and 0.06% or less of Nb, and optionally one or more elements selected from the group consisting of: more than 0% and 0.03% or less of Ti, and more than 0% and 0.01% or less of Mg, with the balance being iron and inevitable impurities, wherein a ratio (Ca/S) of the Ca to the S is 3.0 or more, the Ca, the S, and the O satisfy the formula below: (Ca -1.25S)/O ≤ 1.80, at a stage of the slab, the slab for the steel plate does not include a horizontal crack or includes the horizontal crack having a maximum opening thickness of a threshold value tθ or less, where the threshold value tθ is a maximum opening thickness of a horizontal crack for avoiding the occurrence of hydrogen-induced cracking in the steel plate obtained by rolling the slab, the threshold value tθ is a value previously determined by method including following (i) to (iii): (i) a maximum opening thickness of the slab is measured; (ii) a hydrogen-induced cracking test is performed on a steel plate obtained by rolling a slab which has been cast under the same casting conditions as said slab; and (iii) a maximum opening thickness of a horizontal crack that avoids the occurrence of hydrogen-induced cracking is determined from the maximum opening thickness measured in the step (i) and a result of the hydrogen-induced cracking test shown in the step (ii), wherein the HIC test is performed according to the method specified by the NACE standard TM0284-2003 and wherein the horizontal crack is a crack present in a region ranging from the end to half the thickness D of the slab in the width direction W of the slab and the horizontal crack is the crack that propagates in the slab width direction and the casting direction. 0.02 to 0.15% of C; 0.15 to 0.50% of Si; 0.6 to 2.0% of Mn; more than 0% and 0.030% or less of P; more than 0% and 0.003% or less of S; 0.010 to 0.08% of Al; 0.0003 to 0.0060% of Ca; 0.001 to 0.01% of N; more than 0% and 0.0045% or less of O; 0.0002% or more and 0.0047% or less of REM; and 0.0003% or more and 0.010% or less of Zr; and more than 0% and 0.005% or less of B, more than 0% and 0.1% or less of V, more than 0% and 1.5% or less of Cu, more than 0% and 1.5% or less of Ni, more than 0% and 1.5% or less of Cr, more than 0% and 1.5% or less of Mo, and more than 0% and 0.06% or less of Nb, more than 0% and 0.03% or less of Ti, and more than 0% and 0.01% or less of Mg, (i) a maximum opening thickness of the slab is measured; (ii) a hydrogen-induced cracking test is performed on a steel plate obtained by rolling a slab which has been cast under the same casting conditions as said slab; and (iii) a maximum opening thickness of a horizontal crack that avoids the occurrence of hydrogen-induced cracking is determined from the maximum opening thickness measured in the step (i) and a result of the hydrogen-induced cracking test shown in the step (ii), wherein the HIC test is performed according to the method specified by the NACE standard TM0284-2003 and wherein the horizontal crack is a crack present in a region ranging from the end to half the thickness D of the slab in the width direction W of the slab and the horizontal crack is the crack that propagates in the slab width direction and the casting direction. <EOS>