The present invention aims to provide an antithrombogenic material which is highly safe with its low hemolytic toxicity, and capable of maintaining high antithrombogenicity for a long period. The present invention provides an antithrombogenic material comprising: a coating material containing a polymer containing, as a constituent monomer, a compound selected from the group consisting of alkyleneimines, vinylamines, allylamines, lysine, protamine, and diallyldimethylammonium chloride, and an anionic compound containing a sulfur atom and having anticoagulant activity and a base material whose surface is coated with the coating material wherein the polymer is covalently bound to the base material, and the abundance ratio of nitrogen atoms to the abundance of total atoms as measured by X-ray photoelectron spectroscopy on the surface is 6.0 to 12.0 atomic percent.