The present invention relates to a cutter assembly for a brush cutter. According to the present invention, the cutter assembly for the brush cutter comprises: a top housing placed on a front end of a rotary shaft of the brush cutter to have an exposed hole at a corresponding position of a circumference； a bottom housing combined with a bottom side of the top housing； a winding unit rotatably accommodated in the bottom housing to be combined with the rotary shaft by a screw, wherein a wire cutter is inserted into the exposed hole to penetrate and to be wound on a circumference； an elastic member combined with the bottom housing to elastically support the winding unit towards the top housing； and a winding unit rotary member placed in between the rotary shaft and the top housing to be combined with the winding unit and to, when the wire cutter is inserted into the exposed hole, rotate the winding unit, thereby winding the wire cutter. The winding unit comprises: a winding reel which includes: a protruding unit formed on a top side by penetrating the top housing； and a hollow unit formed on a bottom side to correspond to the protruding unit, and which is rotatably accommodated in between the top housing and the bottom housing to make the protruding unit combined with the winding unit rotary member, to make the wire cutter inserted through the exposed hole wound on a circumference by being combined to penetrate the hollow unit, and to make a shaft combined with a rotary shaft of the brush cutter by a screw inserted into and combined with the protruding unit in a direction of the hollow unit； and a cutter guide duct detachably combined with the hollow unit to guide the wire cutter penetrating the winding reel. The present invention is to provide the cutter assembly for the brush cutter, which is capable of securing a replacement structure which is easy when a shaft is worn out.예초기용 커터 어셈블리가 개시된다. 본 발명의 예초기용 커터 어셈블리는, 예초기의 회전축 선단에 배치되고 둘레의 서로 대응되는 위치에 노출공이 형성되는 상부 하우징； 상기
