Abstract: A method for manufacturing a vibrator includes a preparation step of preparing a quartz crystal substrate having a first surface and a second surface which are in a front and back relationship, a first protective film formation step of forming a first protective film in an element formation region of the quartz crystal substrate at the first surface where the vibrator is formed; and a first dry etching step of dry etching the quartz crystal substrate from the first surface through the first protective film. R1>R2, in which R1 is a thickness of the first protective film in a first groove formation region of the quartz crystal substrate where the first groove is formed and R2 is a thickness of the first protective film in the second groove formation region where the second groove is formed.