An angular velocity sensor amplifies a plurality of detection signals using one amplifying circuit and properly separates these detection signals after amplification. The angular velocity sensor detects displacements of a mass in the respective axial directions using an x-axis detection circuit, a y-axis detection circuit and a z-axis detection circuit respectively. A carrier wave which has a phase thereof shifted from a phase of a carrier wave of the z-axis detection circuit by 90° is applied to the x-axis detection circuit and the y-axis detection circuit, wherein the application of the carrier wave to the x-axis detection circuit and the y-axis detection circuit is performed by switching based on a clock signals. Outputs of the respective axis detection circuits are collectively inputted to a current/voltage conversion circuit. An output signal of the current/voltage conversion circuit is inputted to three synchronous detection circuits, and an x-axis detection signal component, a y-axis detection signal component and a z-axis detection signal component are separated in the respective synchronous detection circuits. In the synchronous detection circuits, by applying phase division processing to the combined signal, the z-axis detection signal component is separated from cross axis detection signal components and, further, by applying time division processing to the signal components based on switching timing of the carrier wave, the x-axis detection signal component and the y-axis detection signal component are separated from each other.