The invention provides a roof lighting device arranged on the top of a house. The roof lighting device includes a skeleton and tempered glass. The skeleton includes at least two skeleton vertical frames arranged in parallel. Each two adjacent skeleton vertical frames are connected by a plurality of skeleton straight beams. The shape and size of the tampered glass correspond to the shape and size of the top of the skeleton. The tempered glass is laid and fixed to the top of the skeleton. The roof lighting device realizes natural lighting of a factory building, and natural light is transmitted directly to the room, which ensures that the room is full of soft natural light, saves lighting energy, reduces cost, and has great promotion and application value.