Monoclinic　BiVO4　with　multiple　morphologies　and/or　porous　structures　were　fabricated　using　the　hydrothermal　strategy.　The　materials　were　characterized　by　means　of　the　XRD,　Raman,　TGA/DSC,　SEM,　XPS,　and　UV-Vis　techniques.　The　photocatalytic　activities　of　the　BiVO4　materials　were　evaluated　for　the　degradation　of　Methyl　Orange　under　visible-light　irradiation.　It　is　observed　that　pH　value　and　surfactant　exerted　a　great　effect　on　the　morphology　and　pore　structure　of　the　BiVO4　product.　Spherical　BiVO4　with　porous　structures,　flower-cluster-like　BiVO4,　and　flower-bundle-like　BiVO4　were　generated　hydrothermally　at　100　degrees　C　with　poly(vinyl　pyrrolidone)　(PVP)　and　urea　(pH　=　2)　and　at　160　degrees　C　with　NaHCO3　(pH　=　7　and　8),　respectively.　The　PVP-derived　BiVO4　showed　much　higher　surface　areas　(5.0-8.4　m(2)/g)　and　narrower　bandgap　energies　(2.45-2.49　eV).　The　best　photocatalytic　performance　of　the　spherical　BiVO4　material　with　a　surface　area　of　8.4　m(2)/g　was　associated　with　its　higher　surface　area,　narrower　bandgap　energy,　higher　surface　oxygen　vacancy　density,　and　unique　porous　architecture.