Hierarchical　WO3　hydrates　have　been　synthesized　via　an　ion　exchange　method　using　Na2WO4　center　dot　2H(2)O　as　a　precursor.　The　morphologies　and　phase　structures　of　WO3　hydrates　can　be　controlled　by　tuning　the　concentration　of　Na2WO4　center　dot　2H(2)O　solution.　The　as-synthesized　urchin-like　WO3　center　dot　0.33H(2)O　and　flower-like　WO3　center　dot　H2O　possess　high　specific　surface　area　and　numerous　adsorption　functional　groups,　such　as　W=O　and　O-H　bonds,　on　the　surface.　These　characteristics　result　in　excellent　adsorption　performance　for　both　organic　dyes　and　heavy　metal　ions　from　wastewater.　The　maximum　uptake　capacities　of　the　urchin-like　WO3　center　dot　0.33H(2)O　for　methylene　blue　and　Pb2+　are　247.3　and　248.9　mg　g(-1),　respectively　and　those　of　the　flower-like　WO3　center　dot　H2O　are　117.8　and　315.0　mg　g(-1),　respectively.　The　formation　mechanism　of　such　hierarchical　mesoporous　urchin-like　WO3　center　dot　0.33H(2)O　and　adsorption　mechanism　are　studied　in　this　paper.