PURPOSE: To provide the format specifying method for a word processor which can print with format designation which is different for each page by a single document file.

CONSTITUTION: The name of a document is designated by a key board connected to the word processor, an overall header area 1 is provided within an external storage device connected to the word processor to give format designation to all the pages that include the name of designated document and should be inputted and a code showing to be a last page to the last page so as to store them, and, furthermore, individual header areas 21 to 22 corresponding to respective pages to be prepared and document storage areas 31 to 32 corresponding to them within the external storage device. A format designation equivalent to one page, a corresponding page, the discrimination of the last page from the others and pointer values of the pages of before/behind and the corresponding page are stored in the individual header areas. Besides, the individual header areas 21 to 22 are made to store document data within the respectively- corresponding document storage areas 31 to 32. Each page is printed by a printer with a format corresponding to a format instruction corresponding to the content of the individual header area.