Patterned Ag thin films were obtained through laser irradiation at ambient conditions. We investigated the effects of laser scanning rate for the structure and optical properties of patterned Ag films. XPS results show that the volume fractions of Ag and Ag2O are dependent on the laser scanning rate. The localized surface plasmon resonance was observed in the as-irradiated samples and increased with the acceleration of the scanning rate. Moreover, with the variations of laser scanning rates and excitation energy, these samples exhibit tunable self-defocusing nonlinearity caused by charge transfer and the enhanced electromagnetic field at the interface between Ag and Ag2O.