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Previous work has shown that peracetic acid and maleic acid (PAM) pretreatment can achieve cellulose enrichment from corn stover by dissolving lignin and hemicellulose, while the degradation products of hemicellulose in the pretreatment liquor of PAM pretreatment were mainly dominated by xylose. However, the degradation of hemicellulose in corn stover during PAM pretreatment was still uncertain. The kinetic features of hemicellulose hydrolysis associated with PAM pretreatment of corn stover was investigated. Time profiles of xylan hydrolysis in the range of 90~120℃ were analyzed by using biphasic model with PA pretreatment as a control. The results indicated that xylan was composed of two different fragments (one for the fast hydrolysis portion and one for a slowly hydrolyzed portion of xylan). Slow-to-hydrolyze fraction of hemicellulose was decreased with the increase of temperature. Compared with PA pretreatment, PAM pretreatment could not only significantly reduce the activation energy of fast-to-hydrolyze xylan and slow-to-hydrolyze xylan to 71.4kJ/mol and 79.1kJ/mol, but also enhance the hydrolysis reaction rate of xylan. The validity of the proposed kinetic model was verified by the experimental data. The obtained information revealed the kinetic mechanism of PAM pretreatment to promote the hydrolysis of hemicellulose, which provided a theoretical basis for efficient hydrolysis and product utilization of the hemicellulose in lignocellulosic biomass.