A　novel　photocatalyst　CdWO4　was　synthesized　via　a　hydrothermal　process,　and　its　high　photocatalytic　activity　was　revealed.　The　influence　of　preparation　conditions　on　crystal　structure,　optical　properties,　and　photocatalytic　activity　of　CdWO4　catalyst　was　investigated.　The　results　showed　that　the　sample　was　irregular　short　rods　with　a　monoclinic　wolframite　structure.　In　photocatalytic　performance,　CdWO4　showed　a　good　ability　toward　the　photodegradation　of　methyl　orange　(MO)　and　Rhodamine　B　(RhB).　The　specimen　prepared　at　pH　=　4　through　annealing　process　had　the　best　activity　in　photodegradation　of　MO　in　aqueous　solution　under　UV　light　irradiation.　But　there　were　no　obvious　differences　in　activity　performance　when　annealing　temperature　was　below　873　K,　indicating　that　the　temperature　had　little　influence　on　photocatalytic　activity　of　CdWO4.