A new family of C-2 functionalized trialkylimidazolium ionic liquids with alkoxymethyl groups were synthesized and characterized. Their physicochemical properties including melting point, thermal stability, viscosity, conductivity, and electrochemical windows were systematically investigated. All of these functionalized trialkylimidazolium ionic liquids were liquids at room temperature, and most of them had melting points lower than -60 degrees C. At room temperature, 24 ionic liquids had viscosities lower than 90 cP, and the viscosities of IM2(1o2)2TFSA and IM1(1o2)2TFSA were 50.3 and 53.3 cP.