Abstrct: In this paper, sixty three wheat genotypes irradiated by γ rays with the doses of 0 Gy, 100 Gy, 150 Gy and 250 Gy, respectively were used to investigate the difference of radiation sensitivity and its molecular mechanism in wheat through germination test and gene expression analysis. The results showed that, based on the damage effect of seedling height, sixty three wheat genotypes could be divided into four categories: i.e., the sensitive (Heyou No.1、Zhongyou 206、Taiyuan 703 et al), the mildom sensitive (Hanxuan No.10、Jimai 20、Zhongmai 175 et al), the mildom insensitive (Dekang 961、Yumai 68、Huaimai 20 et al) and the insensitive (Hengguan 136、Han 6172、Yanzhan 4110 et al). The analysis of expression pattern of the TaKu70 and TaKu80 gene responsed to the γ rays irradiation revealed that there were significant differences in the induced expression amounts in the sensitive genotypes while there were no significant differences between the induced expression amounts of the control group and those of treatment group among the insensitive genotypes. It was concluded that the radiation sensitivity was significantly different in the sixty three wheat genotypes, and the differences upon radiation sensitivity were significantly associated with expression pattern of the TaKu70 and TaKu80 gene responsed to the γ rays among sixty three wheat genotypes.