The present invention relates to a thermoplastic elastomer composition comprising: (a) a block copolymer having a weight-average molecular weight of 80,000 to 1,000,000 which is represented by the general formula (I): A(B-A).sub.n, and/or (A-B).sub.n (I) wherein A is a block of a polymer of a vinyl aromatic hydrocarbon; B is a block of an elastomeric polymer; and n is an integer of 1 to 5, and/or a hydrogenated block copolymer obtained by hydrogenating said block copolymer; (b) a softening agent for hydrocarbon-based rubbers; and (c) an olefin-based resin, said component (a) being contained in an amount of 20 to 80% by weight, and said component (b) being contained in an amount of 20 to 80% by weight, both based on a total weight of the components (a) and (b), and said component (c) being contained in an amount of 1 to 300 parts by weight based on 100 parts by weight of a total amount of the components (a) and (b), and a sheet comprising the thermoplastic elastomer composition and a laminate including the sheet.