Abstract: Objective The aim is to investigate cleaning effect of continuous lasers on pollutants and oxides on the surface of aluminum alloys. Methods A conventional high-power continuous laser was employed to perform in-situ cleaning of either pre-weld region or surface of completed welds by adjusting laser power and scanning speed. The high-energy laser was utilized to fragment and remove contaminants. Results As laser power increased, cleaning effect first enhanced and then diminished. Specifically, insufficient power failed to effectively evaporate or fragment surface contaminants, while excessive power tended to cause secondary burning and oxidation of material surface. Additionally, an excessively high scanning speed reduced overlap rate of the scanned area, thereby impairing cleaning effect. Morphological observations, oxide detection, and pore defect analysis of the cleaned surface demonstrated that this method achieved favorable cleaning results, significantly improved post-weld forming quality, and could serve both as a critical supplement to conventional cleaning methods and as an independent solution when other cleaning approaches were unavailable. Conclusion The oscillating laser scanning method not only enables cleaning of planar welds but also realizes efficient cleaning of curved weld surfaces. It effectively removes contaminants and oxides in the weld zone, which holds positive significance for multi-layer multi-pass welding and additive manufacturing processes.