A damping force detecting apparatus for detecting a damping force of a variable damping force type shock absorber including a cylinder and a piston slidably inserted thereinto. The damping force detecting apparatus comprises a piezoelectric element assembly for generating a charge corresponding to a pressure applied thereto and a pressurizing device for pressurizing the piezoelectric element assembly. The piezoelectric element assembly has a diameter smaller than a cylindrical piston rod fixedly secured to the piston and is housed therein. The pressurizing device is screwed into the piston rod so as to be in contact relation to the piezoelectric element assembly for pressurizing the piezoelectric element assembly in correspondance with a distortion of the piston rod generated in the sliding directions of the piston with respect to the cylinder due to expanding and contracting action of the shock absorber.