Force and moment exerted on the working point (P) on a semiconductor substrate (110, 210), on one surface of which resistance elements (r, R) having an electric resistance varying due to mechanical deformation are formed, are detected. A portion spaced from the working point of the semiconductor substrate is fixed. Since openings (113) or bridge portions (212 to 215) are formed in the semiconductor substrate, when a force or an angular moment in a fixed direction is applied to the working point, uneven stresses are produced on the semiconductor substrate. Such uneven stesses are detected as changes in electric resistances of the resistance elements. A measure is taken for an arrangement of resistance elements on the semiconductor substrate, thereby to constitute predetermined bridges. Thus, forces in three directions and angular moments in three directions in the three-dimensional space can be independently read as bridge voltages, respectively.