The invention provides a composition for forming shock absorption foamed plastic. The composition is prepared from a base material component, a foaming agent, a bridging agent and a foaming aid. The base material component comprises a main base material and an auxiliary base material. The main base material is prepared from a styrene-ethylene-butadiene-styrene segmented copolymer and silicone rubber. The auxiliary base material is prepared from a polymer. The polymer is an ethylene-vinyl acetate copolymer or polyethylene or polyacrylate rubber or polyvinyl acetate or a composition of the former substances. The shock absorption foamed plastic formed by the composition for forming the shock absorption foamed plastic in the following process is not subjected to brittle fracture when impacted in a low-temperature environment, and good shock absorption capacity is kept.