Abstract: A stylus has a detection element support part 1E for supporting and fixing piezoelectric elements 21 to 24 and a rod 1D placed on the detection element support part 1E. The detection element support part 1E has a plurality of flange parts 1F each being regular polygonal in cross section orthogonal to the axis of the rod 1D. The displacement detection elements are attached to the sides of the flange parts 1F in a state in which they are inclined at a predetermined angle &agr; relative to the axis of the rod 1D. If a measured force in a torsion direction Q or in a bend direction P occurs on the rod 1D through a contact ball 1A, the measured force is transmitted along substantially the length direction of the piezoelectric elements 21 to 24.