Zr-doped,　Al-doped,　and　Zr-Al　co-doped　ZnO　photocatalysts　were　prepared　via　a　hydrothermal　synthesis　method　and　subsequent　calcination　treatment.　The　structure　and　spectral　properties　of　the　prepared　photocatalysts　were　investigated.　The　photocatalytic　activity　of　the　prepared　catalysts　was　evaluated　by　the　photocatalytic　degradation　of　acid　orangeIIunder　an　ultraviolet　light　(λ=254　nm)　irradiation.　The　results　show　that　the　products　prepared　are　a　hexagonal　wurtzite　structure　of　ZnO.　Compared　to　pure　ZnO,　the　photocatalytic　activity　of　Zr-doped,　Al-doped,　and　Zr-Al　co-doped　ZnO　photocatalyst　samples　had　a　greater　improvement,　and　the　photocatalytic　performance　of　the　Zr-Al　co-doped　ZnO　was　significantly　better　than　that　of　Zr　or　Al-doped　ZnO.　The　increased　photocatalytic　activity　for　the　Zr-Al　codoped　ZnO　sample　could　be　attributed　to　that　the　Zr-Al　co-doped　ZnO　photocatalyst　had　the　more　OH　groups　on　the　surface　of　doped　sample　than　the　pure　ZnO.　The　co-doping　could　effectively　suppress　the　recombination　of　photo-generated　electron-hole　pairs,　thus　favoring　the　improvement　of　photocatalytic　activity　and　stability　of　ZnO.