To provide an acceleration sensor without being damaged due to a temperature change.

The acceleration sensor comprises a displacement section 3 displaced relative to a fixed section 2. The displacement section 3 is displaced due to the acceleration of gravity, and a displacement amount of the displacement section 3 is measured by a resultant change of a capacitance between the fixed section 2 and the displacement section 3. A plurality of external connecting terminals 11, 12 are provided in the fixed section 2, and one of the external connecting terminals 12 is made capable of shaking against the fixed section 2. Accordingly, even if there is a difference in a coefficient of linear expansion against a substrate on which the acceleration sensor is mounted, the external connecting terminals 12 shakes, a large force is not imposed on the fixed section 2 and any damages can be avoided.