The invention relates to a cutting device, in particular to an iron wire cutting device for building construction. The invention aims to solve the technical problem so as to provide the iron wire cutting device for building construction, so that time and labor are saved, iron wires have no need to be cut manually, and people is prevented from getting hurt. The invention provides the technical scheme that the iron wire cutting device for building construction comprises a bottom plate, support legs, a support plate, a movable block, a cutter, a fixing plate, an L-shaped plate and the like, wherein the support legs are symmetrically arranged on the left side and the right side of the bottom part of the bottom plate; the support plate is arranged on the left side of the top part of the bottomplate; the movable block is rotatably arranged on the top part of the support plate; a cutter seat is arranged on the left side of the bottom part of the movable block; the cutter is arranged in the cutter seat; and the fixing plate is arranged on the left side of the top part of the bottom plate, and is located under the cutter. According to the iron wire cutting device for building constructionprovided by the invention, through a fixing device, the occurrence of the phenomenon that a rotating plate rotates to influence the cutting of an iron wire can be prevented; and through the action ofguiding wheels, the occurrence of the phenomenon that the iron wire is deviated so as not to be cut can be prevented, and the effects that time and labor are saved, iron wires have no need to be cut manually, and people is prevented from getting hurt are achieved.