The present invention is directed to an aesthetically improved lateral part of a sunroof for a vehicle configured to conceal an opening/closing mechanism from inside a vehicle to improve the external appearance and marketability. The invention is constructed so not to change prior-installed parts and designs. The sunroof comprises a guide rail frame mounted between a roof panel and a head liner, an opening/closing mechanism mounted at both lateral surfaces of the guide rail frame, a panel support rail for being opened and closed by the opening/closing mechanism, and a decoration cover coupled to a lateral surface of the support rail and for concealing the opening/closing mechanism. The decoration cover is formed in a predetermined length for coupling to a lateral surface of the glass support rail and has a predetermined height for concealing the opening/closing mechanism.