The invention provides a piezoelectric small beam test piece including a piezoelectric device which comprises piezoelectric ceramic as a base. An electrode is arranged on the periphery of the piezoelectric ceramic. A support is disposed on the bottom surface of the electrode. A cap is arranged on the top surface of the piezoelectric ceramic. The small beam test piece is cut into appropriate sizes according to testing needs. The piezoelectric device is arranged on the bottom surface of the small beam test piece. Each piezoelectric device is connected with an indicator part. The invention also provides a production method and a testing method of the piezoelectric small beam test piece. The invention designs an energy accumulator for small beam testing and provides a corresponding testing method. The testing method can be used to deeply study the deformation mechanism and energy accumulation power of a built-in road surface structure under the load effect and provide testing instructions for engineering applications.