To discuss the preparation and reflective spectral properties of two-dimensional aluminum-doped zinc oxide (ZnO:Al) gratings on back contact mental Al, a thickness of 80 nm ZnO:Al thin film was deposited on 300 nm Al substrate, then a layer of AZ5206 photo-resist was spin coated on ZnO:Al thin film. Mask pattern was acquired with 325 nm laser holographic lithography. Using lift off technology, two-dimensional ZnO:Al gratings with 624~1 250 nm periods and 100~300 nm heights on Al substrate were acquired. Grating periods and heights could be regulated independently. Surface morphologies were observed by atomic force microscopy and scanning electron microscopy, reflection spectrum was tested using spectrophotometer with integrating sphere, bidirectional reflectance distribution function was measured by scattering instrument. Results showed that total reflectivity, diffuse reflectivity and haze of those gratings with 228 nm heights all increased obviously as periods increasing from 624 nm to 986 nm. As periods increasing from 986 nm to 1 250 nm, the increment of total, diffuse reflectivity and haze were only small. The tested results of bidirectional reflectance distribution functions further confirmed the above conclusions, namely more large periods, more large diffuse reflectivity peak value, and more peak position numbers. It was concluded that back contact ZnO:Al grating with 986 nm period and 228 nm height had excellent scattering effects, such as the percentage of diffuse reflectivity to total reflectivity was up to 45%.