A piezoelectric fan embedded in a fin heat sink is proposed and the numerical simulation and experimental investigation are carried out in this paper. The characteristics of the unsteady flow field induced by the piezoelectric fan and the enhanced heat transfer performance were analyzed. The influences of external airsupply velocity and fin pitch on the flow field and heat transfer performance are studied. The results indicate that, because of the extrusion, disturbance of the piezoelectric fan and the presence of vortexes, the thermal boundary layers of the fin surface are disrupted, the fluid mixing and heat transfer is enhanced, and the temperature gradient of the fluid decreased, thereby the fintoair heat transfer resistance decreased significantly. When the fin pitch is 18 mm, the piezoelectric fan presented in this paper has the best heat dissipation effect.