To provide a thermoplastic resin composition comprising a urethane-based thermoplastic elastomer and a thermoplastic elastomer composition rich in flexibility and excellent in heat distortion resistance, molding processability and compatibility with a urethane-based resin, to provide a molded form thereof, and to provide a composite molded form thereof.

The thermoplastic resin composition comprises 100 pts. wt. of (A) the thermoplastic elastomer composition comprising (a) 100 pts. wt. of an elastomer comprising a block copolymer composed of at least two polymer blocks A based on an aromatic vinyl compound and at least one polymer block B based on a conjugated diene compound and/or a hydrogenated block copolymer thereof, (b) 5-300 pts. wt. of a flexibilizer for rubber, (c) 0.01-3 pt(s). wt. of an organic peroxide and (d) 1-80 pt(s). wt. of a hydroxyl-terminated liquid polybutadiene and 10-1,500 pts. wt. of (B) the urethane-based thermoplastic elastomer. This thermoplastic resin composition is to be used for composite molding with a polyacetal resin. The molded form and the composite molded form each obtained using the above thermoplastic resin composition are also provided respectively.