A piezoelectric device includes: a piezoelectric vibrating reed; and a package, wherein the piezoelectric vibrating reed has a vibrating part and first and second supporting arms extending from a base end part, the package has a base, a lid, a cavity defined by the base and the lid, a convex part projecting from the base or the lid into the cavity, a length of the first supporting arm is shorter than a length of the second supporting arm, and the convex part is provided in a range ahead of a leading end of the first vibrating arm in an extension direction of the first supporting arm and at least partially overlapping with the second supporting arm in a length direction of the piezoelectric vibrating reed so as not to overlap with the piezoelectric vibrating reed in a plan view.