Provided is a method for manufacturing a high-quality piezoelectric vibrator in which reliable air-tightness of the inside of the cavity is maintained, and stable conduction between the piezoelectric vibrating reed and the outer electrodes is secured. The manufacturing method includes a penetration hole forming step of forming a plurality of penetration holes 30 on a base substrate wafer 40; a core portion insertion step of inserting core portions 7 of a rivet member 9 into the penetration holes from one side of the wafer; a melting step of bringing the rear surface of the base portion 8 of the rivet member into contact with the wafer to close the opening end on the one side of the penetration holes, heating the wafer while pressing the other side of the wafer so as to melt a surface portion on the other side of the wafer to produce a liquid base substrate material 41, and causing the material to flow into gaps between the inner circumferential walls of the penetration holes and the rivet member from the other side of the penetration holes so as to close the gaps; a curing step of cooling and curing the material poured into the gaps; and a polishing step of removing the base portion and polishing the wafer and the rivet member so that the base substrate wafer and the core portion are planarized.