Abstract: 【Objective】 This study first comprehensively evaluated the heat resistance of 24 Gossypium hirsutum germplasm resources. 【Methods】 Based on the two-year comprehensive evaluation of heat resistance D value cluster analysis.Selecting 24 cotton germplasm materials.Randomized block design.Measurement of relevant indicators. 【Results】 It was found that 24 Gossypium hirsutum resource materials could be divided into 3 categories.The first category was heat-resistant materials, the second category was intermediate-type materials, and the third category was heat-sensitive materials.An evaluation model for the heat resistance of Gossypium hirsutum was established through a stepwise regression equation: D=-0.111+0.175X₂+0.470X₃+1.211X₄ (R²=0.914,8).According to the established optimal regression equation, the heat resistance of Gossypium hirsutum materials, the comprehensive evaluation indexes of cotton heat resistance were established.Correlation analysis and difference analysis found that seed cotton yield, boll weight and lint yield could be used as evaluation indicators of cotton field heat resistance, while plant height and lint had nothing to do with heat resistance. 【Conclusion】 In this study, four heat-resistant Gossypium hirsutum resource materials were selected, and the seed cotton yield, boll weight and lint yield were established as the indicators for evaluating the field heat resistance of Gossypium hirsutum, and the peroxidase, malondialdehyde and chlorophyll content were used indoors.The index of heat resistance evaluation provides a reference for the rapid breeding of heat-resistant cotton varieties and the research of cotton heat-resistant mechanism.