Adorning apparatus and headwear using the same

An apparatus for adorning a size control portion, formed in at least one of lower lateral sides of an opening portion of headwear according to an exemplary embodiment of the present invention includes an adorning portion having at least one face that is 3-dimensionally adorned, a support portion connected to the adorning portion to support the adorning portion, and a detachable coupling portion formed in a part of the support portion and detachably coupled to the size control portion. According to the present invention, an apparatus for freely and variously adorning a size control portion provided in a lower edge portion of a head receiving portion of headwear at low cost, and the adorning apparatus can be used in headwear.