Abstract: For understanding the radiation sensitivity of different crops to ⁶⁰Co γ radiation, 7 crop varietals dry seeds, cotton, rice, barley, rape, soybean, glutinous corn and sweet corn, has been exposed in the 0~1500Gy 60Co γ radiation. The germination rates, with the exposure time in the γ ray increased, present following 4 kinds of type. the results showed that rape, insensitive; (2) rice and soybean, the germination rate gradually decrease; (3) cotton and barley, germination rate "decrease - increase - decrease again", but the highest germination rate does not surpassed the control; and (4) glutinous corn and sweet corn, the germination rate "increase-decrease", germination rates reach maximum when the exposure is 300Gy. The exposure sensitivity is ranked in: rice > soybean > cotton > glutinous corn, sweet corn> barley > rape. Therefore, authors suggested the crops exposure sensitive difference in ⁶⁰Co γ rays was mainly decided by the crop genomic size and seed fullness besides rape contains the chemical Component called allyl mustard oil which resistant to radiation.