Disclosed is a composite formed by physical and chemical bonding of (a) a carbon nanotube (CNT); and (b) a metal complex with at least one kind of ligand coordinated to a central metal, the CNT being connected to the metal within the metal complex by a direct bond to the metal. Also, provided is a dispersant for a CNT containing a metal complex comprising (i) a complex ion with at least one kind of ligand (Ln) chemically bonded to a central metal; and (ii) a counter ion. By using a metal complex as a dispersant for a CNT, various characteristics possessed by the metal complex can be provided to the CNT, and the dispersibility of the CNT can be meaningfully increased by introducing a ligand and/or a counter ion having dispersion medium-affinitive properties.