The invention discloses a monocrystaline silicon damage-free tunneling window integration method for promoting SONOS data holding ability. The method comprises the following steps: performing tunneling window dry etching; using phosphorus element in the tunneling window to perform channel injection; performing high-temperature annealing, injecting repairing ions in the damage of a substrate; performing tunneling window oxide film wet etching, and using hydrofluoric acid as wet liquid medicine which can not damage the surface of the substrate. By using the method of the invention, the tunneling oxide film generated by subsequent oxidation has smooth interface, the probability of aggrandizement of local electric field is reduced, and the probability of reverse tunneling of electrons is reduced. Therefore, the charge storage capacity is increased and the written or erased threshold voltage window is improved.