An inkjet ink contains water, a hydrosoluble organic solvent, a pigment, polyvinyl pyrolidone, and a copolymer, wherein the copolymer contains a structure unit represented by Chemical formula 1, where R1 represents a hydrogen atom or a methyl group, R2 is an alkyl group having one to four carbon atoms, M1+, M2+, M3+, and M4+ each, independently represent protons, alkali metal ions, or organic ammonium ions, and a structure unit represented by Chemical formula 2, where R3 represents a hydrogen atom or a methyl group, a structure unit represented by Chemical formula 3, where R4 represents a hydrogen atom or a methyl group, or a structure unit represented by Chemical formula 4, where R5 represents a hydrogen atom or a methyl group.