This paper presents atmospheric pressure liquid densities and viscosities for mixtures of diethylene glycol + water over the entire composition range at temperatures from (283.15 to 353.15) K. Density is measured using a vibrating tube densimeter, and two different Cannon-Fenske viscosimeters are used for the viscosity measurements. The excess molar volumes are calculated from experimental measurements. Excess molar volumes present negative deviations from ideality at all the investigated temperatures and become more negative with decreasing temperature. From (293.15 to 343.15) K, the viscosity deviation as a function of composition changes sign from negative to positive in the water-rich region. A Redlich-Kister-type equation correlates the viscosity deviations.