A new methodology is proposed to measure the dielectric constant and loss of a piezoelectric at the resonance frequency range based on the burst excitation method. Using a k(31) type soft PZT rectangular specimen, we investigated the force and voltage factors carefully under the short- and open-circuit conditions of the burst method, in terms of the ratio of the ring-down current and voltage with the plate end vibration velocity and the displacement, and their phase lags. We provide the obtained material properties, including loss parameters, in particular, dielectric properties at the resonance frequency range.