The invention provides a sky curtain roof structure of a building, and relates to the field of electronic sky curtains. The sky curtain roof structure of the building comprises a skylight structure, a sky curtain frame and an electronic sky curtain, the skylight structure is arranged at a courtyard of the building, and when the skylight structure is opened, internal and external ventilation of the building can be achieved; a window shade is installed on the inner side of the skylight structure and movably connected with the skylight structure so that the window shade can be adjusted to be folded or unfolded. The skyscreen frame is fixed on the lower side of the skylight structure, the skyscreen frame is composed of metal rods, a hollow area is arranged in the skyscreen frame, and the electronic skyscreen is installed on the lower side of the skyscreen frame; the electronic backdrop comprises a plurality of light-emitting lamp strips which are arranged side by side at intervals, ventilation and lighting intervals are formed between the adjacent light-emitting lamp strips, and the skylight structure, the hollow area of the backdrop frame and the ventilation and lighting intervals of the electronic backdrop are communicated up and down to form a ventilation and light-transmitting channel. The sky curtain roof structure integrates the decoration and practicability of the electronic sky curtain, and meets the requirements of natural lighting and internal and external ventilation.