A semiconductor force sensor capable of preventing a diaphragm part from being broken and accurately measuring a force applied thereto in a direction orthogonal to the diaphragm part, wherein a force transmitting device for applying a measured force to the diaphragm part of a semiconductor force sensor element is formed of a sphere having a rigidity, and a through hole passing through an opposed wall part toward the diaphragm is formed in the opposed wall parts at a position opposed to the center part of the diaphragm part so that a part of the sphere can face the outside of the opposed wall part and stores a part of the remaining part of the sphere to allow the sphere to be moved only in a direction orthogonal to the diaphragm part and rotated on the center part of the diaphragm part.