1. A piezoelectric vibrating piece, comprising:a vibrating piece body, including a vibrator; and
at least a pair of excitation electrodes, being formed on a front surface and a back surface of the vibrator, respectively,
wherein the vibrating piece body is a doubly rotated quartz-crystal vibrating piece cut out parallel to an X?-Z? surface, the X?-Z? surface being rotated around a Z-axis of a crystallographic axis of a crystal and further rotated around an X?-axis; and
the pair of excitation electrodes are collocated in a Z??-axis direction determined by an X??-axis, the X??-axis being defined by counterclockwise rotation from a +X?-axis direction around a Y?-axis by 260° to 300°, the pair of excitation electrodes being disposed inclined with respect to an Y?-axis direction.