Density is one of the key physicochemical properties for sugar solutions. The objective of this work is to model the density of sugar solutions. The density calculation has been carried out by applying statistical associating fluid theory (SAFT) equations of state. This new method made use of critical temperature, pressure, and volume as well as normal boiling temperature to determine the SAFT parameters for sugars and is now extended to determine the SAFT parameters for D-xylose, sucrose, and sorbitol. The critical properties and normal boiling temperature of sugars are estimated based on information of molecular structure. The densities of sugar solutions including binary systems of D-glucose/H2O, D-fructose/H2O, D-xylose/H2O, sucrose/H2O, and sorbitol/H2O; ternary systems of D-fructose/H2O/ethanol and sucrose/sorbitol/H2O; and quaternary systems of D-glucose/D-fructose/H2O/ethanol have been calculated without using binary interaction parameters. Results with high accuracy have been obtained. Finally, the water activity of sorbitol/water and xylitol/water and the normal boiling temperature of glucose/water and fructose/water have been modeled.