Olefin Block Copolymers (OBC), an elastomer whose main raw materials are 1-octene and ethylene, is prepared by controlling the ratio of ethylene and octene through polymerization reaction to produce an olefin copolymer with alternating "soft segments" and "hard segments." Due to its multi-block structure, OBC has superior properties, higher melting temperature, lower glass transition temperature, high elasticity, easy processing, fast crystallization rate, high tensile strength, etc. It is an elastic material with broad application prospects.