Abstract: An improved decorative lighting system constructed having a support framework assembly for mounting decorative lights in connection with a window frame. The support framework assembly comprises a plurality of tubular track members, each formed having a slotted chamber section extending the length of the track member with a squared outer edge formed along either side at the base of the chamber to provide a substantially flat planar surface along the base of the track member. A plurality of articulating end clips are formed to engage each track member and interconnect with another to join the track members in a substantially rectangular configuration adjustable to conform to the shape of the window frame. A plurality of specially configured light mounting clips are formed to press-fit and slide along the flat perimeter surface of the track members and hold the decorative lights in selected positions along the track members.