Separation of oligosaccharides with a varied number of monosaccharides is an important issue in the food chemistry. Raffinose, a functional oligosaccharide, has attracted increasing attentions due to its strong proliferative effect on bacteria. Industrially, cottonseed meal is an important resource for producing raffinose; however, raffinose extracted from the cottonseed meal contains a significant amount of sucrose that debases the raffinose's quality. In this work, an adsorptive separation of raffinose and sucrose on activated carbon was reported. Adsorption isotherms, adsorption kinetics, and dynamic column adsorption-desorption were investigated. The activated carbon chosen has a significantly higher adsorption capacity of raffinose (0.60~0.65 g/g) than sucrose (0.35~0.40 g/g) at the equilibrium concentration studied (~35 g/L) and temperature from Downloaded by [University of Leeds] at 21:22 04 June 2016A c c e p t e d M a n u s c r i p t 2 293 K to 333 K. Adsorption isotherms and kinetics were fitted by Freundlich isotherm model and pseudo-second-order model, respectively. The effect of flow-rate and initial feed concentration on the dynamic adsorption were investigated, meanwhile, the separation performance was further confirmed from the dynamic desorption using aqueous ethanol of 20% as eluant. Remarkably, raffinose with purity over 90% and recovery of 79.2% could be obtained by adsorption-desorption cycle using the aqueous feed solution containing 20 g/L of raffinose and 6 g/L of sucrose.