A novel shape memory polymer material was fabricated by γ-ray irradiating the blending thermoplastic styrene-butadiene-styrene block copolymer (SBS) with low density polyethylene (LDPE), and SBS/LDPE=80/20. The relationship between the structure and shape memory properties of SBS/LDPE blends was investigated by the analysis of gelation level, DSC, mechanical properties and shape memory performances. The results show that with increasing absorbed dose, the gelation level of SBS/LDPE blends increases, meaning that the degree of cross-linking of SBS/LDPE blends increases; while the tensile strength of blends and the elongation at break decrease gradually. In addition, the radiation cross-linked SBS/LDPE blends exhibited good shape memory effect, and the shape recovery ratio is more than 95%.Cited