A speaker includes: a frame, a vibration system, including a diaphragm and a voice coil driving the diaphragm to vibrate and emit sounds, and a magnetic circuit system fixed to the frame, including a lower plate, and a central magnetic portion and an auxiliary magnet fixed to the lower plate, the central magnetic portion spaced apart from the auxiliary magnet, the auxiliary magnet surrounding the central magnetic portion and forming a magnetic gap, the voice coil located in the magnetic gap, wherein the central magnetic portion includes a main magnetic portion and a reinforcing portion surrounding the main magnetic portion, a projection of the voice coil in a vibration direction of the diaphragm is at least partially located in the reinforcing portion. Compared with the related art, the speaker disclosed by the present disclosure could improve the BL value of the voice coil.