A thermoplastic resin composition including a first thermoplastic polymer and a second thermoplastic polymer, wherein the first thermoplastic polymer is a block copolymer including a plurality of polymer blocks, at least one of the plurality of polymer blocks includes a random copolymer, and at least one structural unit of the first thermoplastic polymer and a structural unit of the second thermoplastic polymer are stereoisomers, a molded article made therefrom, and methods of making the same.