<P><B>Abstract</B></P> <P>A process concept combining pretreatment of wood in ionic liquids and subsequent enzymatic hydrolysis to sugars is herein investigated to identify operating conditions which allow for (i) the processing of larger wood chips of 10mm length, (ii) low temperature, (iii) high sugar yield, and (iv) short processing time. A careful quantitative study of the interaction of pretreatment and hydrolysis reveals that hydrolysis is most effective if beech chips are first disintegrated in [EMIM][Ac] at 115°C for 1.5h. The cellulose conversion varies between 70.5wt% and 90.2wt% for hydrolysis times between 5h and 72h. A complete recovery of cellulose and xylan resulting in a total saccharification of 65wt% of the wood chips could be demonstrated. It is shown that short pretreatment times are required to enable high sugar yield as well as to limit product degradation.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Effective enzymatic hydrolysis of wood chips disintegrated by [EMIM][Ac]. </LI> <LI> Pretreated chips of beech provide twice the yield of sugars as compared to spruce. </LI> <LI> Quantitative yield of cellulose and xylan from beech chips pretreated at 115°C. </LI> <LI> Conversion of more than 70% of cellulose and 65% of wood into sugars within 5h. </LI> <LI> Longer pretreatment results in degradation products leaching into soluble sugars. </LI> </UL> </P>