PURPOSE: To prevent the change of an output signal due to the atmospheric temp. of an installation place by a simple method mutually negating the irregularity of the output signals of the same displacement of a magnet, by arranging a plurality of magnetic response elements so as to be capable of generating output signals in mutually reverse directions with respect to the displacement of the magnet.

CONSTITUTION: Both left-hand and right-hand spaces 2, 3 are formed in the cylindrical casing 1 made of a non-magnetic material of an acceleration sensor by a partition wall 4. A permanent magnet 5 is arranged to the upper end of the cantilevered beam member 6 fixed to the housing 9 in the space 2 and damper oil 12 is sealed in the space 2. Hall IC13, 14 each comprising a magnetic response element are arranged to the space 3 corresponding to the magnet 5 of the space 2 and constituted of single Hall elements 16, 17. IC13, 14 are arranged so as to be capable of outputting signals in mutually reverse directions with respect to the magnet 5 and the irregularity of the output signals of the same displacement of the magnet 5 is negated to prevent the change of an output signal due to the atmospheric temp. of an installation place.