Nano-porous anodized aluminum oxide (AAO) films were prepared by secondary anodization, and these AAO films were subjected to argon ion treatment with different sputtering durations by radio frequency (RF) sputtering. FE-SEM, XRD, and ATR-FTIR were used to study the morphology and structural characteristics of the AAO films. The photoluminescence (PL) spectra of the AAO films were studied with variable wavelengths of excitation light, the results show that the argon ion treatment has a significant effect on the microstructure and the PL properties of the AAO films. The influence of argon ion treatment on the microstructure and the relationship between the PL properties is discussed.