The thermoplastic resin composition of the present invention contains a thermoplastic resin (A) and carbon black (B), wherein the thermoplastic resin (A) contains a graft copolymer (C) in which a vinyl-based polymer is grafted to a rubber-like polymer, the carbon black (B) has a volume average particle size of secondary particles of 200 nm or more, and a proportion of secondary particles having a particle size of 800 nm or more with respect to the entire secondary particles of less than 20% by volume, and a content of the carbon black (B) is from 0.1 to 3.0 parts by mass with respect to 100 parts by mass of the thermoplastic resin (A).