A multi-magnet speaker is disclosed. The multi-magnet speaker includes a frame defining a hollow space, a magnetic system defining a yoke and a plurality of magnetic gaps positioned in the hollow space, a diaphragm mounted on the frame and a plurality of coils attached to the bottom of the diaphragm. The diaphragm includes a plurality of vibrating membranes each defining a dome part and an arcuate portion radially extending from the periphery of the dome part. Each of the coils is received in the corresponding magnetic gap to drive the corresponding vibrating membrane to vibrate.