As Metal-core Piezoelectric Ceramic Fibers (MPFs), one types of the new piezoelectric devices, have smaller structrures and sizes, it is difficult to find proper mesurement method and corresponding measuring fixture. Therefore, this paper proposed a precise and easily operated method to measure the MPFs. First, the test model was deduced by using the constitutive equations of a MPF, and the measuring steps for electrical performance of the MPF were established. Then, the effect of test fixture on the measurement results was investigated. Experiments show that it is easy to produce deviation when the clamping positions in the middle of the MPF, which can influence the measurement results . When the clamping position is at the end of the MPF, the relative admittance values of resonance and anti-resonance frequency are smaller, which is hard to be measured either. Furthermore, an improper clamping pressure have a strong effect on the measured value due to the smaller size of MPF. Finally, a measurement method without clamping for the MPF was presented. By the proposed methd, the PZN-PZT MPFs were measured, obtained results give the piezoelectric property values by piezoelectric strain d31 of -97pC/N, electromechanical coupling coefficients k31 of 0.197, and dielectric constant ε33T of 1 458. This kind of method is accurate, simple operation, and not damage to MPFs, and can be used as a test standard for MPFs.