The rates of water absorption of three maizes, dent (PIONEER 3379), semident (ICI RF67) and flint (CARGILL T-42), in plain water and 0.25% SO2 aqueous solution were studied. The steeping temperatures were 45, 55 and 65-degrees-C. The absorption kinetics in plain water and SO2 solution follows a ＇Fickian＇ behavior (moisture content of the kernels varies with the square root of time) during the first hours of steeping. The rates of absorption in SO2 solution were slightly higher than in plain water at all temperatures, even though at the onset of steeping, the SO2 seemed to retard the rate of absorption. This increase was relatively higher for flint and semident types than for dent maize. The activation energies for water sorption in SO2 solution were lower than for plain water, this effect being more marked for flint and semident types.