In this research, the vibration characteristics of bolt single-lap joint of two aluminum plates are investigated in both experimental and finite element methods. The finite element results are obtained using the nonlinear steady-state dynamic analysis via ABAQUS software. To present a more realistic finite element model for dynamic simulation of bolted joints, the interaction surface at interfaces of the two plates is simulated utilizing nonlinear elastic-plastic contact elements with zero thickness. A laboratory model of this structure is constructed, and its natural frequencies are extracted for various amounts of applied torque on bolts. Afterwards, the finite element model is updated using the direct method and the effectiveness of the finite element model is evaluated by actual experimental data. After model updating, the effect of bolt preloads on the frequency response function and vibration characteristics of the response signal, including natural frequencies, energy parameter, kurtosis and standard deviation are investigated. The results indicated that there is acceptable compatibility between the results of the finite element model and the experimental tests. Additionally, it can be concluded that for the bolt loosening defects identification, processes in the time domain, and application of energy-based signal parameters, standard deviation, and kurtosis of the vibration signals are more appropriate rather than natural frequencies analysis.