Abstract: A built-up dome lamp frame, mainly composed of two locating rods and one or more link rods to extend the frame length, wherein one of the locating rods comprises a locating channel on one side and a track channel on the other side; said locating channel being for the fixation of the locating tongue of the other locating rod or the link rod so as to let the track channel of each locating rod be able to connect with a support; said support being fixed to a proper location within the respective track channel so as to let clamping devices match with each adjusting element to fix the whole frame body onto the dome of the car.