An opener mechanism in which a label folded in a sheet shape is opened and fitted to a target body is provided with first suction rods which suck one side of a label, second suction rods which are arranged to oppose the first suction rods and suck the other side of the label, and a drive mechanism which induces movement of the first and second suction rods toward or away from each other. Suction hole arrays in which a plurality of suction holes which suck the label are aligned in a line are formed on the surfaces facing one another of the first suction rods and the second suction rods. The suction holes are arranged in such a manner that the suction hole arrays of the first suction rods and the suction hole arrays formed in the second suction rods opposing the first suction rods are at least partially nonparallel.