To provide an angular velocity sensor having reduced CI by enhancing drive efficiency of tuning fork vibration.

The angular velocity sensor includes a tuning fork-shaped crystal piece, having a pair of tuning fork arms extended from a tuning fork base part, drive electrodes provided on major surfaces and side surfaces of the tuning fork arms for exciting tuning fork vibration, sensor electrodes provided to the tuning fork arms, and also serving as reference electrodes for the drive electrodes, and detecting charges generated due to angular velocity; and a monitor electrode provided to the tuning fork-shaped crystal piece and detecting an amplitude of the tuning fork vibration, with the monitor electrode being provided near a fork part of the pair of tuning fork arms, wherein the fork part is the tuning fork base part.