A gyro sensor includes a plurality of beams connected via a turnaround part. A groove is provided on a main surface of at least one beam of the plurality of beams. Wall thicknesses on the main surface of two sidewalls facing each other of the groove in a direction orthogonal to a longitudinal direction of the beam satisfy 0.9≤T1/T2≤1.1, where T1 is the wall thickness of one sidewall and T2 is the wall thickness of the other sidewall.