The present invention reduces the value of a bonding width L of a base substrate and a lid substrate in each piezoelectric vibrator. The method comprises the steps of forming a plurality of base substrates each comprising two penetrative electrodes (7) with a wafer (40) for base substrate and disposing piezoelectric vibrating strips (4) on the base substrates (2); forming a plurality of lid substrates (3) each comprising a recess (3a) with a wafer (50) for lid substrate and forming bonding films (35); manufacturing a wafer unit (60) formed by a plurality of piezoelectric vibrators (1) through butt joint and anode joint of the wafer (40) for base substrate and the wafer (50) for lid substrate; and applying laser light along cutting lines of the piezoelectric vibrators (1) on the side of the wafer (50) for lid substrate for adding microgrooves (813) and pressing the microgrooves from the opposite side with a pressing blade (830) for cutting, thereby splitting the wafer unit (60) thoroughly with high efficiency through pressing the microgrooves on the opposite side.