Heat tolerance of wheat is a complex quantitative trait controlled by multiple genes. Molecular markers related to heat tolerance can be acquired by correlation analysis. With these tolerant markers，the accuracy of molecular marker-assisted selection breeding may be improved，and the process of breeding for heat tolerant wheat may be accelerated. In this study，heat sensitivity indexes (HI) of five grain traits，including 1000-kernel weight，kernel length，kernel width，kernel surface area，and kernel circumference were identified in 190 wheat varieties (lines). Molecular markers Xwmc622 and Xwmc707 related to heat sensitivity indexes were obtained by simple correlation analysis. Polyacrylamide gel electrophoresis analysis showed that Xwmc622 and Xwmc707 each had three allelic types: I，II and III. Type I allelic loci of Xwmc622 were extremely significantly negatively correlated with HI of 1000-kernel weight，of kernel width，and of kernel circumference (all P < 0.01)，and significantly negatively correlated with HI of kernel length and of kernel surface area (all P < 0.05). The average values of HI in wheat varieties (lines) with type I allelic variation were less than 1. Type II allelic loci of Xwmc622 were extremely significantly positively correlated with HI of 1000-kernel weight (P < 0.01)，and significantly positively correlated with HI of kernel length，of kernel surface area，and of kernel circumference (all P < 0.05). The average values of HI in wheat varieties (lines) with type II allelic variation were greater than 1. Type III allelic loci of Xwmc622 were not correlated with HI of grain traits. Type I allelic loci of Xwmc707 were not correlated with HI of wheat grain traits. Type II allelic loci of Xwmc707 were significantly negatively correlated with HI of 1000-kernel (P < 0.05). The average values of HI in wheat varieties (lines) with type II allelic variation were less than 1. Type III allelic loci of Xwmc707 were significantly positively correlated with HI of 1000-kernel weight，of kernel width，and of kernel circumference (all P < 0.05). The average values of HI of the grain traits in wheat varieties (lines) with type III allelic variation were greater than 1. The results showed that allele I of Xwmc622 and allele II of Xwmc707 were superior alleles of wheat heat tolerance，which provided reference information for molecular marker-assisted breeding for wheat heat resistance.