The objective compounds, benzyltriethylammonium tetrafluoroborate([Nbz222]BF4), benzyltriethylammonium hexafluorophosphate([Nbz222]PF6), benzyltriethyl-ammonium hydrogen sulphate([Nbz222]HSO4), benzyltriethylammonium dihydrogen phosphate ([Nbz222]H2PO4), and benzyltriethylammonium imidazolideintermediate([Nbz222]Im) were designed and synthesized by anion exchange reaction of the intermediate benzyltriethylammonium chloride which was prepared using triethylamine and benzyl chloride as starting materials. All the compounds including the quaternary ammonium-type ionic liquids(ILs) were characterized by FT-IR, 1H NMR, 13C NMR, ESI-MS and element analysis respectively. Meanwhile, the physical properties of the ILs were investigated. It was found that the melting points of the ILs are below 100℃ except for [Nbz222]PF6. The TG results indicated that the thermostability of [Nbz222]HSO4 is higher than the others associated with the decomposition temperature decrease in the orders of [Nbz222]HSO4 > [Nbz222]BF4 > [Nbz222]Im > [Nbz222]H2PO4. In addition, the ILs exhibited water absorption and were miscible well with polar solvent.