A ring-shaped illuminating apparatus with variable projection angle includes a fixing ring, a plurality of swing plates and a plurality of light elements. The fixing ring is connected to the camera. The swing plates each have a fixing end pivotally connected to the fixing ring and a free end away from the fixing end. The swing plates can change their status from an opened status to a closed status. While in the closed status, the free ends of the swing plates are close to each other. While in the opened status, the free ends of the swing plates are away from each other. Each of the swing plates has an inner face and an outer face opposite to the inner face. The inner faces of the swing plates face to each other in the closed status. The light elements are respectively arranged on the inner faces of the swing plates.