The sub-wavelength artificial metamaterials which demonbstrate nearly-perfect absorption of a specific wavelength can overcome the defects of low absorption efficiency, large thickness, and working wavelength limitation of band gap in the infrared photoelectric device application. In this paper, a metal/medium/metal structure is used to construct a sub-wavelength structure that can be prepared over a large area, which can achieve dual-band infrared perfect absorption in the 1-10 μm band. Through analyzing the results of Finite-Difference Time-Domain simulation and experiment, we believe that the high-frequency absorption peak of the absorber is mainly derived from FP resonance interference enhanced absorption; while the absorption peak in the low-frequency infrared band is mainly due to the excitation of the electric dipole resonance and the magnetic resonance mode. By adjusting the size of the upper layer of gold particles in the way of annealing, the positions of the two absorption peaks can be effectively regulated.