A flexible substrate having flexibility and a fixed substrate disposed to oppose it are supported at their peripheral portions by a sensor casing. An oscillator is fixed on the lower surface, and five lower electrode layers are formed on the upper surface, of the flexible substrate. Five upper electrode layers are formed on the lower surface of the fixed substrate so as to oppose the lower electrodes. In detecting an angular velocity ωx about the X-axis, an a.c. voltage is applied across a predetermined pair of opposite electrode layers to allow the oscillator to undergo oscillation Uz in the Z-axis direction. By change of capacitance, it is possible to detect the magnitude of the Coriolis force Fy, and determine angular velocity ωx Similarly, it is possible to detect an angular velocity ωy about the Y-axis and an angular velocity ωz about the Z-axis.