The present invention provides an alloyed molten zinc plated steel sheet having an area of the Fe and Zn alloy phase in the unformed parts in the plating layer of less than 10% of the area of the steel sheet as a whole and superior in strength and shapeability and a method of producing this alloyed molten zinc plating steel sheet by a continuous zinc plating production system which enables production at a low cost without modification of the system or addition of steps, said alloyed molten zinc plated steel sheet characterized by comprising a steel sheet including C: 0.05 to 0.40%, Si: 0.2 to 3.0%, and Mn: 0.1 to 2.5%, the balance comprised of Fe and unavoidable impurities, having on its surface a Zn alloy plating layer comprised of Fe in a concentration of 7 to 15 wt %, Al in a concentration of 0.01 to 1 wt %, and the balance of Zn and unavoidable impurities, said plating layer containing oxide particles of at least one type of oxide selected from an Al oxide, Si oxide, Mn oxide, and complex oxides of the same alone or in combination.