To provide a structure that absorbs differences between sheets of electronic paper and corresponding products, thereby enabling a product and a system which are mounted with electronic paper to function widely.

In an image forming system 1, the electronic paper 400 includes: a profile information providing means 2 for holding and providing information about a transfer format and procedure required for reading and writing with respect to the electronic paper; a communicating means 6B for providing the profile information or transferring/receiving image data; a format reversely converting means 5 for converting image data transmitted from an image forming apparatus 100, into a form matching display; and a control means 20B. The image forming apparatus 100 has: a profile information acquisition means 3 for acquiring profile information; a communicating means 6A; a format converting means 4 for converting image data to be displayed on the electronic paper into a transfer format that matches writing on the electronic paper; and a control means 20A.