Abstract: Impedance testing of piezoelectric materials could obtain the resonant frequency and model parameters of the equivalent circuit of piezoelectric oscillators. Test the performance of piezoelectric materials at room temperature and low temperature of liquid nitrogen. The results show that there were significant differences in the resonant frequency, dielectric constant, electromechanical coupling coefficient, dielectric loss of different piezoelectric materials at room temperature and low temperature of liquid nitrogen. In the low temperature environment of liquid nitrogen, the resonant resistance, resonant frequency, and dielectric loss of piezoelectric materials increased to varying degrees, while the dielectric constant and planar electromechanical coupling coefficient decreased to varying degrees. The low temperature environment of liquid nitrogen would have an irreversible impact on the dielectric loss of BaTiO₃ and strontium titanate.