An image forming apparatus includes a supplier and an inkjet head. The supplier supplies, to a medium to be printed, a dye-transfer suppression agent that suppresses a dye or a pigment dyeing chemical fibers constituting the medium to be printed from transferring to a print surface formed on the medium to be printed. At least one of a platen on which the medium to be printed is placed or the supplier is moved to supply the dye-transfer suppression agent to the medium to be printed. The inkjet head ejects ink for forming the print surface to an area to which the dye-transfer suppression agent is supplied.