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Stress relaxation is one of important rheological characteristics of corn stalk compression bale, affecting compression deformation, productivity and power consumption. Cellulose, hemicellulose and lignin content of 13 different varieties of corn stalks in matured from Beijing, Liaoning, Shandong, Hubei, Shaanxi and Chongqing were measured. Compression and stress relaxation of corn stalks were implemented in the selfmade cylinders by universal testing machine INSTRON3367. The stress relaxation times and balance elastic modulus were gotten by fitting stress relaxation curves of corn stalks, and were treated as assessment indicators of stress relaxation properties. Gray correlation analysis was applied in the relevance between the stress relaxation properties of corn stalks and the lignocellulose ingredients. The results showed that differences among cellulose, hemicellulose and lignin contents of different varieties of corn stalks were highly significant (P<0.05). It was found that hemicellulose and lignin contents were highly correlated with stress relaxation properties of corn stalks, while the cellulose content of corn stalks was little effect on stress relaxation properties. From a microscopic point of view, correlation degrees of cellulose, hemicellulose and lignin content associated with stress relaxation properties depended on their regions and functions in the cell wall.