Acceleration sensor

The acceleration sensor is formed of a cylinder; an inertial member slidably mounted in the cylinder so as to be movable in the longitudinal direction of the cylinder; a conductive member fixed at least on an end surface of the inertial member facing one longitudinal end of the cylinder; a pair of electrodes fixed relative to the cylinder at one longitudinal end of the cylinder and which, when the conductive member of the inertial member makes contact with the electrodes, are caused to conduct via the conductive member; and an attracting member fixed relative to the cylinder near the other longitudinal end of the cylinder, for magnetically attracting the inertial member. The electrodes are formed by a metal sheet whose basal ends are held by an electrode holding member and whose front ends are protruding in the travel area of the inertial member, and one of planes of the metal sheet is disposed so that it faces to the inertial member. In the acceleration sensor, the edge portions of the sheet metal forming the electrode are bent in the direction opposite to the inertial member.