Abstract: Under the mechanically free and clamped boundary conditions, electromechanical resonances of ceramic multilayer capacitors are calculated using vibration and piezoelectric equations. Multilayer capacitors made of ferroelectric BaTiO3 and Pb(Mg1/3Nb2/3)O3 ceramics have been used to examine the theoretical calculation. Frequency spectra of impedance and phase angle, capacitance and loss tangent of the capacitors under dc bias fields are carefully measured. A sudden change around the resonant frequency is observed in these spectra. A damped resonance indicates a defective capacitor while an undamped resonance is corresponding to defect free.Experimental results suggest that it is possible to use the spectra as a real time nondestructive evaluation method.