In this work, the cellulose-hemicellulose interaction during pyrolysis was investigated to study the impacts of sample preparation, temperature, mixing ratio on the light products distribution. Cellulose-hemicellulose interactions were studied by Py-GC-MS with different temperatures (500, 600, 700 degrees C), mixing ratios (mass ratio 1:1 and 5:2), and mixing methods (physical and native mixtures). Generally speaking, cellulose-hemicellulose interaction would significantly promote the formation of hemicellulose-derived products and CO2, while inhibit part of cellulose-derived products, especially the formation of levoglucosan. Moreover, the native cellulose-hemicellulose mixture had the most distinct impact on the product distributions. A statistic method has been used to evaluate the strength of cellulose-hemicellulose interaction and compared with cellulose-lignin interaction, finding that mixing method had the strongest influence on cellulose-hemicellulose interaction, followed by temperature, and mixing ratio had the weakest influence. Most importantly, the interaction between cellulose-hemicellulose was weaker than cellulose-lignin. (C) 2016 Elsevier Ltd. All rights reserved.