Recyclable biocatalysts and highly efficient lignocellulose degradation are the decisive factors for a cost-effective conversion of biomass into biofuels and bioproducts. The catalytic hydrolysis of acetic acid-based grassy lignocellulosic biomass is a promising application because of its effectiveness, recyclability and other environmentally friendly properties. However, this treatment is not as effective on woody biomass such as poplar. One way to improve the conversion performance of this process is to integrate it with other effective methods, such as. In this work an integrated acetic acid-based one-pot ethanolamine acetate pretreatment (HAc–[EOA] [OAc] ) was developed for the efficient depolymerization of poplar polysaccharides. The configuration simultaneously removed ~ 88% hemicellulose and selectively extracted up to ~ 46% of the lignin from lignocellulosic biomass. HAc–[EOA] [OAc] Pretreated poplar yielded over 80% enzyme-hydrolyzed glucose, which was attributed to an increase in the accessible surface area of the cellulose for the hydrolytic enzymes. Analysis of cellulose crystallinity and thermal degradation profiles revealed that all pretreated samples had higher cellulose crystallinity, suggesting that amorphous cellulose was removed during the pretreatment. A ladder-like real solvent screening model (COSMO-RS) and Hansen solubility parameters (HSP) were used to provide insight into the mechanism of biomass pretreatment effectiveness using HAc and [EOA] [OAc] . We found that a strong hydrogen bond and electrostatic mismatch between hemicellulose and HAc may explain the greater removal of hemicellulose during HAc pretreatment. In addition, the near HSP values and the COSMO-RS analysis indicate that [EOA] [OAc] is a good lignin solvent that leads to higher delignification of biomass. This study shows that the integration of IL with acidic pretreatment is a promising strategy to perform an effective pretreatment of woody lignocellulose.