Strontium　barium　niobate　SrxBa1-xNb2O6　(SBN)　nanocrystals　with　different　components　(x=0.2,　0.4,　0.6,　and　0.8)　were　synthesized　by　Molten　Salt　Synthesis　(MSS)　method　at　various　reaction　temperatures　(T　=　950°C,　1000°C,　1050°C,　and　1100°C).　The　SBN　nanocrystals　yielded　through　flux　reactions　possess　different　morphologies　and　sizes　with　a　length　of　about　100　nm7　μm　and　a　diameter　of　about　200500　nm.　The　Scanning　Electron　Microscopy　(SEM)　and　X-ray　Diffraction　(XRD)　techniques　were　used　to　study　the　compositions,　structures,　and　morphologies　of　the　nanocrystals.　The　absorption　edges　of　the　SBN　nanocrystals　are　at　a　wavelength　region　of　approximate　390　nm,　which　corresponds　to　band-gap　energy　of　3.18　eV.　The　SBN　nanocrystals　with　different　sizes　display　different　photocatalytic　activity　under　ultraviolet　light　in　decomposition　of　water.　The　SBN60　nanocrystals　exhibit　stable　photocatalytic　rates　(100130　μmol　of　H2·g-1·h-1)　for　hydrogen　production.　The　SBN　nanocrystals　can　be　a　potential　material　in　the　application　of　photocatalysis　and　micro/nanooptical　devices.　©　2017　Guoqiang　Han　et　al.