<p>In this letter, a new laser cleaning method in archaeology using surface plasmon-polariton (SPP) mode on copper surface is proposed and found to have high cleaning efficiency. Commonly, the copper cultural relics may have a layer of patina or other dirt such as dielectric oil on the surface. The SPP mode in the ultraviolet region, guided by the interface between copper and patina, is first reported and used to remove patinas and other dirt on the surface of copper cultural relics to the best of our knowledge. This mode shows negative loss contribution and anomalous dispersion in our considered UV region, while they don’t show in other wavelength bands. The SPP mode in the UV region was rarely reported before this research because of the huge loss and very short propagation length, however, they are advantages used in laser cleaning especially in archaeology. We believe this work can provide valuable fundamental theory predictions for applying laser cleaning in archaeology using SPP mode in the UV band.</p>