Angular velocity sensor

An angular velocity sensor is manufactured by simple method and has reduced size and height. It includes a base portion (1) formed by a piezoelectric single crystal and having a length in the Y-axis direction and a thickness in Z-axis direction; and four beams (2a-2d) each extending in the Y-axis direction perpendicular to the X- and Z-axis directions, that are arranged side by side in the X-axis direction and formed by the same piezoelectric single crystal as the base portion. The four beams (2a-2d) are grouped in two pairs (2a, 2b; 2c, 2d), with one of each pair (2a, 2d) used as a drive beam and the other (2b, 2c) as a counterbalance. The drive beams (2a, 2d) are provided with drive electrodes (3a1, 3a2; 3b1, 3b2) adapted to oscillate the beams in the X-axis direction and Y-axis sensing electrodes adapted to detect the rotation angle applied around the Y-axis, and the other beams serving as counterbalances are provided with X-axis sensing electrodes adapted to detect the rotation angle applied around the X-axis.