A speaker includes a holder, a magnetic circuit unit, and a vibration unit including a diaphragm, a voice coil, and a centering support plate. The centering support plate is fixed to a side of the voice coil facing away from the diaphragm. One end of the centering support plate fixed to the voice coil is provided with a pad electrically connected to the voice coil. The diaphragm includes a central portion, a suspension portion surrounding the central portion, and a dome fixed to the central portion. The dome includes a body attached to the central portion, and a connection portion extending from an edge of the body towards the pad and fixedly connected to the pad. With the connection portion, the pad of the centering support plate can be fixed, preventing the tone quality of the speaker from being damaged by the pad, and t reducing noise.