A thermoplastic resin composition for vehicle lamp housings, includes: 5 to 80 parts by weight of a graft copolymer (A) obtained by graft polymerizing at least one monomer (a-2) selected from the group consisting of aromatic vinyl-based monomers, vinyl cyanide-based monomers, and (meth)acrylic ester-based monomers and maleimide-based monomers, under the presence of an acrylic ester-based rubbery polymer (a-1) having a weight average particle size of 100 to 400 nm; and 20 to 95 parts by weight of a (co)polymer (B) in which at least one monomer (a-2) selected from the group consisting of aromatic vinyl-based monomers, vinyl cyanide-based monomers, (meth)acrylic ester-based monomers and maleimide-based monomers is polymerized, in which a content of total volatiles at 260° C. is no more than 0.7% by weight of the composition overall, and a content of oligomer component having a weight average molecular weight of 200 to 1000 is no more than 0.3% by weight of the composition overall.