Provided is a carbon nanotube dispersion composition including carbon nanotubes, a dispersant, and a solvent and satisfying (1) and (2) as follows: (1) an average outer diameter of the carbon nanotubes calculated from an SEM image obtained by observing the carbon nanotubes included in the carbon nanotube dispersion composition is 15 nm or more and 50 nm or less; and (2) when a target pixel group in the SEM image obtained by observing the carbon nanotubes included in the carbon nanotube dispersion composition is set as the carbon nanotubes, and a value obtained by dividing an absolute maximum length by a length of a free curve, that is, a skeleton length, is set as linearity, a proportion of carbon nanotubes with a linearity of 0.9 or more among carbon nanotubes with a skeleton length of 1 m or more is 40% or more and 90% or less.

There is provided a carbon material dispersion wherein even when it contains a high concentration of a carbon material, the dispersibility of the carbon material is excellent and the dispersibility is retained stably over a long period of time. The carbon material dispersion contains: at least one carbon material selected from the group consisting of carbon black, carbon fibers, carbon nanotubes, graphite, and graphene; water; and a polymeric dispersant, wherein the polymeric dispersant is a polymer having carboxy groups at least part of which are neutralized with an alkali, the polymer having 50 to 80% by mass of a constituent unit (1) derived from (meth)acrylonitrile and 20 to 50% by mass of a constituent unit (2) derived from (meth)acrylic acid, provided that the total amount of the constituent unit (1) and the constituent unit (2) is 100% by mass, and the polymer has a number average molecular weight of 10,000 to 50,000.