Abstract: A technology for writing information that varies by object into electronic tags. An electronic tag writing system that includes a writing device that writes writing information into electronic tags; and an information acquisition part that reads writing information and a processing order out of a storage part that stores the processing order in association with writing information for objects that are associated with the electronic tags. The writing information that is associated with the processing order acquired by the information acquisition part is written into the electronic tags by the writing device in accordance with the processing order.