The radiation effect of ethylene-vinyl alcohol copolymer (EVOH), EVOH/glycerin blend was studied by solvent extraction, gel permeation chromatography (GPC) and Fourier transform infrared spectrum (FTIR) methods. Samples were irradiated up to 1800kGy at room temperature under N,2,. The results show that degradation is the main reaction in pure EVOH. Trace gel content could be found in E151 irradiated to at least 800kGy, and only 5.9% gel content was found in the sample irradiated to 1200kGy.While trace gel content could be found in F101 irradiated to at least 1800kGy. The different gelation doses of E151 and F101 are due to different contents of vinyl alcohol units. Unsaturation structure can be found in the irradiated EVOH. The content increased at first, and then decreased, with the dose. The existence of double bond enhances the radiation efficiency of EVOH. For EVOH/glycerin blend, the gel content was than that of pure EVOH when the absorbed dose exceeds 800kGy, and the gel content increased with the absorbed dose. But it cannot enhance radiation efficiency of EVOH as water.