Purpose <p>In order to meet the vibration isolation and power supply requirements in automobile seat suspensions, a high-performance vibration isolation and energy harvesting integrated system with quasi-zero stiffness characteristics is proposed based on the piezoelectric buckling beam structure.</p> Method <p>The equation of piezoelectric buckling beam is established by using the principle of virtual work, the differential equation of motion is established by Newton’s second law, and the electromechanical coupling equation of the system is obtained by combining Ohm’s law. The frequency-domain dynamic vibration isolation and energy harvesting characteristics of the integrated system are studied by harmonic balance method, and the dynamic response of the seat suspension to vibration isolation and energy harvesting in the time domain under different road excitations and different vehicle speeds is analyzed by the Runge–Kutta method.</p> Results <p>Frequency-domain analysis shows that the integrated system can achieve vibration isolation and energy harvesting over a wide frequency range. Time-domain analysis shows that the integrated system can effectively mitigate road impact, achieve vibration isolation, and collect energy on various road surfaces, including bumpy and random road surfaces.</p> Conclusion <p>Through the comparative analysis of different electromechanical coupling coefficients, different damping ratios and different road surface incentives, it is found that appropriately increasing the electromechanical coupling coefficient and reducing the damping ratio will be beneficial to the isolation and energy harvesting performance of the system.</p>