In this work, we proposed a new aqueous biphasic system composed of hydrophilic ionic liquids (IL, 1-butyl-3-methylimidazolium tetrafluoroborate) and saccharides, forming an upper IL-rich phase and a lower sugars-rich phase. It was found that that the distance between binodal curves and the origin is the increasing. order of sucrose < glucose < xylose < fructose, which was successfully elaborated in terms of the stereochemistry of saccharides and hydration models. Compared with the IL + inorganic salts systems, the proposed systems are more environmentally benign for separating IL from the aqueous phase.