The densities and viscosities of 1-butyl-3-methylimidazolium tetrafluoroborate [Bmim][BF(4)] ionic liquid with methyl formate, methyl acetate, ethyl formate, and acetone have been measured at 298.15 K. The excess molar volume V(m)(E) and the viscosity deviations Delta eta for the binary mixture have been calculated and were fitted to the Redlich-Kister polynomials. The values of V(m)(E) and Delta eta are negative over the whole composition range. The minima in V(m)(E) and Delta eta are observed at about mole fraction of the ionic liquid, x approximate to 0.3 and 0.7, respectively.