A trimmer head having an upper case having a fastening portion formed with an upper fastening hole for coupling the rotating shaft to a center of the upper case; a lower case formed with a lower fastening hole at its center and the lower case being coupled to the upper case; a body portion positioned in a cavity between the upper case and the lower case; and a plurality of cutting means coupled to the body portion so as to be rotatable at one end thereof, wherein the upper case and the lower case are further connected to each other by a plurality of elastic media and are spaced apart by the tension of the elastic medium when the upper case and the lower case are separated from each other.