A large-area high-performance near-infrared absorber based on plasmonic nanostructures is introduced, fabricated and experimentally characterized.The periodic plasmonic nanostructures are prepared by self-assembled template, a charming low-cost technology for making large-area samples.Experimental results showthat the absorbance can be as high as 99%.The spectral position of the absorption peak is experimentally demonstrated to be tuned by the geometric dimensions.The physical origin of the absorption effect is theoretically explained as well.