Disclosed is a thermoplastic elastomer composition that will provide little load on the environment and has superior mechanical characteristics, the composition being obtained by melt-kneading 10 to 90 parts of ethylene-α-olefin based copolymer rubber (A), 1 to 50 parts of non-petroleum source-derived thermoplastic resin (B), 0.01 to 20 parts of modified ethylene-based copolymer (C), 1 to 50 parts of propylene-based polymer (D), 0.001 to 5 parts of crosslinking agent (E), and 0 to 50 parts of a mineral oil-based softening agent (F), wherein the amounts of components (A), (B), (D) and (F) are amounts in weight calculated where the total amount of components (A), (B), (D) and (F) is considered to be 100 parts, and the amounts of components (C) and (E) are amounts in weight calculated where the total amount of components (A), (B), (D) and (F) is considered to be 100 parts.