A nail cosmetic composition contains a silicone macromonomer as a base material having at least two polymerizable functional groups and a polymerization initiator with respect to the silicone macromonomer. A method of using a nail cosmetic composition includes a painting step of painting a nail cosmetic composition described above on a nail and a curing step of exposing the nail cosmetic composition to light with an illuminance of 80 mW/cm2 or less at dominant wavelength at an exposure time within three minutes per one layer to cure the nail cosmetic composition. The nail cosmetic resin contains a silicone unit in which a silicone macromonomer has been polymerized as the base material having at least two polymerizable functional groups.
