A flash structure for the camera function of a handheld electronic device having at least a camera module as well as an image sensor and a camera lens contained in the camera module, comprising an outer cover, an annular reflector, at least a light diffuser, and one or a plurality of fixed light-emitting elements which are light emitting diodes or electronic flashes to provide continuous or intermittent supplemental light source. The center of the annular reflector passes through the camera lens and is formed on the motherboard of the handheld electronic device, and is arranged with a through-slot. The one or the plurality of light-emitting elements are embedded in the through-slot of the annular reflector, arranged around the camera lens, and electrically connected to the motherboard. The light diffuser is disposed outside the annular reflector, outside the light-emitting element and positioned around the camera lens.