Abstract:To make clear the relationship between the secondary metabolites and the resistance of cotton to Apolygus lucorum Meyer-Dür, the resistance levels of different cotton varieties to A.lucorum were evaluated in the field, and the content of condensed tannin, flavonoids and terpenoids were also measured by H2SO4-Vanillin assay and high performance liquid chromatography (HPLC) method in laboratory, respectively. The result indicated that the content of secondary metabolites in different tissues along developmental stage were significantly different among various cotton varieties. It was found that the content of condensed tannin, total terpenoids and total heliocides of cotton leaves at seedling stage had significant positive correlation with host resistance to A.lucorum. There was a positive correlation between the rutin content and host resistance to A.lucorum in leaf and bud at budding stage, while the content of isoquercitrin and quercetin of boll at bolling stage had a negative correlation with host resistance to A.lucorum. The result suggest that cotton with more condensed tannin, rutin, total terpenoids and total heliocides could be used to minimize the damage by A.lucorum, however, the isoquercitrin and quercetin can cause A.lucorum occurred.