The invention belongs to the field of electronic science and technology, relates to an MEMS (Micro-Electro-Mechanical System) piezoelectric resonator and provides a piezoelectric resonator with two narrow support beams and a high quality factor. The piezoelectric resonator comprises a vibration block, an input end support beam, an output end support beam, an input end support table, an output end support table and a base, wherein the vibration block is electrically connected to the support tables through the support beams; the support tables are arranged on the base; external metal electrodes are arranged on the support tables; the vibration block is formed by an input end P type semiconductor area and an N type semiconductor area, wherein the input end P type semiconductor area is arranged at a connection place of the vibration block and the input end support beam; the support beams for connecting the areas of the vibration blocks and the corresponding areas of the vibration block adopt the same doping type; a piezoelectric layer partially covers the vibration block; a notch is partially exposed out of the input end P type semiconductor area; and a metal electrode arranged on the piezoelectric layer is connected to the input end P type semiconductor area through a transition metal electrode. According to the structure, the width of the support beams can be greatly reduced and the quality factor Q of the resonator can be effectively improved.