Dynamic excitation of a clogged fracture can increase its permeability. Pressure oscillations inside the fracture are expected to flush out the fine particles blocking the flow. The objective is to improve the performance of gas and oil wells by cleaning the fractures previously generated by hydraulic fracturing as the circulation of sediments during service tend to clog them. Yet, more investigations shall be conducted to understand the mechanism better. This experimental study investigates the unclogging process of a propped fracture previously clogged, using a synthetic dynamic load. Laboratory experiments are presented. Fractures are clogged with crushed natural sand. All the permeability measurements are performed under uniaxial stress of 20 MPa to mirror real operating conditions. After applying the dynamic load, a significant increase of the intrinsic permeability is observed. The highest recovery rate reached was 82%. The influence of the proppant density, of the proppant size, and of the frequency of the dynamic signal are discussed. X-ray CT scans provide images of the fracture before and after the dynamic load has been applied. The results show that a high percentage of fines are flushed out of the fracture.