The ionic liquid,1-ethyl-3-carboxymethylimidazolium tetrafluoroborate was synthesized with 1-ethylimidazole based on the single-mode microwave synthesizer.The structure of the product was characterized,and underwent a thermal analysis.Its properties such as viscosity,density,surface tension and electrochemical window were also measured.Meanwhile,the solubility of starch in ionic liquid was investigated.The results showed that the microwave irradiation has the advantages of fastness,short reaction time and mild reaction condition.The yield of the product is 88.23%.Its properties of density,viscosity and surface tension have linear relationships with temperature,respectively.Compared with water,the ionic liquid has a higher solubility for starch soluble,which provides a theoretical basis for the homogeneous derivatization reaction of starch and its derivatives.