Pretreatment using ethylene glycol was investigated to enhance the enzyme digestibility of wastepaper. The pretreatment was conducted over a wide range of conditions including sulfuric acid concentrations of 1.3 ~ 4.7%, temperatures of 143.2 ~ $176.7^{circ}C$ and reaction time of 1.6 ~ 18.4 min. The optimum conditions were around 2% sulfuric acid, $150^{circ}C$ and 15 min. At these conditions, 60 and 75% of hemicellulose and lignin, respectively, were removed while cellulose remained intact. Additionally, an enzyme digestibility of 94% was achieved. From the substrate dissolution analysis, the dissolution yield was strongly related to the enzymatic digestibility and the removal of cellulose, hemicellulose and lignin. Also, the dissolution yield was directly related to the severity parameter, which provides a quantitative prediction of the intensity of a reaction. Recycling and re-use of ethylene glycol were also studied. Ethylene glycol could be recycled and re-used at least four times without significantly lowering the pretreatment performance.