A thermoplastic resin composition comprising a polylactic acid polymer (A), an acrylic polymer (B) containing units of methyl methacrylate monomer, and a graft copolymer (C) obtained by graft-polymerizing a vinyl monomer onto a rubbery polymer, wherein the refractive index, Rc, of the graft copolymer (C) and the total refractive index, Rab, of the polylactic acid polymer (A) and the acrylic polymer (B) satisfy the following formula (1)−0.004≦Rc−Rab≦+0.008 (1).