An acceleration sensor having a novel structure by which acceleration measurement of high precision and reliability can be implemented. A monocrystalline silicon substrate (1) is joined to a monocrystalline silicon substrate (8) through an SiO2 film (9). The monocrystalline silicon substrate (1) is a thin film. A cantilever (13) is formed on the monocrystalline silicon substrate (1). The thickness of the cantilever (13) in the direction parallel to the surface is smaller than that in the depth direction of the monocrystalline silicon substrate (1). The cantilever is movable in the direction parallel to the surface of the substrate. The surface of the cantilever (13) and the surface of the monocrystalline silicon substrate (1) which faces the cantilever (13) are covered with an SiO2 film (5) in order to prevent the electrodes of the capacitance type acceleration sensor from being short-circuited. A signal processing circuit (10) is formed on the monocrystalline silicon substrate (1) to process signals produced by the movement of the cantilever (13). <IMAGE>
