Effect of degree of acetylation (DA) within corn stalk (CS) on the enzymatic hydrolysis was investigated. By acetylation and deacetylation treatment, CS with different DA from 0.34% to 11.20% was prepared. The analysis of chemical composition by two-step acid hydrolysis and characteristic functional groups via FTIR implied that the structure of the three major components (cellulose, hemicellulose and lignin) in the treated CS was not changed noticeably. The correlation between enzymatic yield and DA was navigated well by the nonlinear curve fit with Adj. R-Square greater than 0.90. The DA was proved to be a crucial barrier to the digestibility of CS. The efficiency of the enzymatic hydrolysis was negatively correlated with DA value. (C) 2014 Elsevier Ltd. All rights reserved.