A galvanized steel plate including a base steel sheet and an alloyed zinc coat layer formed on at least one surface of the base steel sheet. The alloyed zinc coat layer includes columnar grains made of [zeta] phase and containing more than 0% and equal to or less than 5% of Fe, and more than 0% and equal to or less than 1.0% of Al. Twenty percent or more of the entire interface between the alloyed zinc coat and the base steel sheet is covered by the [zeta] phase. Among [zeta] phase grains in the alloyed zinc coat layer, [zeta] phase grains containing large oxides make interfaces with the base steel sheet that account for equal to or less than 50% of the entire interface between the [zeta] phase and the base steel sheet. The base steel sheet has predetermined chemical compositions, and has a fine-grain layer that is directly adjacent to the interface between the base steel sheet and the alloyed zinc coat layer. The average thickness of the fine-grain layer is 0.1 to 5.0 [mu]m. The average grain diameter of ferrite in the fine-grain layer is 0.1 to 3.0 [mu]m. The fine-grain layer contains one or combination of more than two oxides of Si and Mn. The maximum diameter of the oxides is 0.01 to 0.4 [mu]m. The base steel sheet contains 1% or more by volume of residual austenite in the depth range from the surface thereof from 1/8 to 3/8 of the thickness thereof 1/4 of the thickness being the center.