A flame-retardant wood flooring material manufacturing method and a wood flooring material produced by the same are provided to improve incombustibility by deeply penetrating a flame retardant into the wood instead of applying the flame retardant on the surface of the wood. A flame-retardant wood flooring material manufacturing method comprises the steps of: expanding voids of wood(50) by disposing the wood in a vacuum state; making the grains of wood smooth for penetration of a flame retardant by steaming the wood; lowering the temperature of the heated wood down to 10~50 degrees and expanding the voids of the wood by vacuum-treating the wood again; impregnating the wood with the flame retardant by dipping; pressing the wood by high pneumatic pressure; deeply penetrating the flame retardant into the wood by heating the wood with steam; washing and dewatering the wood; drying the wood at 10~40 degrees by natural drying or using a dryer; and completing the flooring materials to be assembled, by cutting the processed wood.