A wire reel for rebar tying machine including a reel and a wire wound therearound and an engagement portion at which an earlier-wound part of the wire may be engaged with a later-wound part of the wire by the later-wound part of the wire sinking below the earlier-wound part of the wire. A manufacturing method of a wire reel for rebar tying machine includes: fixing one end of a wire to a reel; winding the wire around the reel by feeding the wire while rotating the reel; and stopping the feeding of the wire while rotating the reel to cause a later-wound part of the wire to sink below an earlier-wound part of the wire such that the later-wound part of the wire engages with the earlier-wound part of the wire.