A miniature speaker is disclosed. The miniature speaker includes a frame, a magnetic circuit unit positioned by the frame and forming a magnetic gap, and a vibration unit. The vibration unit includes a vibration plate having a diaphragm including a central portion, a periphery suspending the diaphragm, a suspension surrounding the central portion with an edge connecting to the periphery, a stiffener located on the central portion, a border located on the central portion and surrounding the stiffener, and a voice coil including an inner side and an outer side opposed to the inner side. The border and the stiffener cooperatively form an interval therebetween. The stiffener controls the high frequency vibrations, and the border controls the low frequency vibrations.