Pellet and thermoplastic resin composition

Provided is a carbon black master batch pellet for black coloring comprising a high concentration of carbon black, having an excellent dispersibility of the carbon black, and which can express a stable black coloring concentration with hardly any classification occurring even when mixed in the various raw materials of a thermoplastic resin composition. A pellet comprising 35 to 55 mass % of carbon black (A), 65 to 45 mass % of a thermoplastic resin (B), and 0 to 10 mass % of a dispersant assistant (C), wherein a diameter (D) in a direction orthogonal to the axial direction is 2 to 5 mm, and a ratio (D/L) of the diameter (D) to a length (L (mm)) in the axial direction is 3.0 to 1.5.