An angular velocity sensor amplifies a plurality of detection signals using one amplifying circuit and separates these detection signals after amplification. The angular velocity sensor detects displacements of a mass in the axial directions using x-, y- and z-axis detection circuits. A carrier wave whose phase is shifted 90° from that of a carrier wave of the z-axis detection circuit is applied to the x- and y-axis detection circuits and outputs of the axis detection circuits are collectively inputted to a current/voltage conversion circuit which outputs a combined signal to three synchronous detection circuits that separate the signal into x-, y- and z-axis detection signal components. 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 by applying time division processing to the signal components based on switching timing of the carrier wave, the x- and y-axis detection signal components are separated from each other.