In this study, barley germination test was carried out in an apparatus that could simulate low-dose X ray environment, and the quality parameters of barley were detected to analyze the relationship between the radiation dose received by barley seeds and the germination process of barley. The study found that the X ray of barley seed germination stage of bud length, root length and biomass to produce inhibition, accept the dose of 1 059.65 μSv/s experimental Ⅰ starch, protein and fat in 3 days delay. which compared with the control group increased 19.8%, 31.6% and 33.3%, respectively and the soluble dietary fiber was reduced by 41.8%. The degree of change was positively related to the intensity of X ray, but X ray effect on germination rate were not significantly. The effect and mechanism of X ray on germinated food were explained and confirmed.