PURPOSE: To obtain a pi-character code processing system in which a defect that the sorts of pi-characters in format data are limited by a memory capacity for a pi-character font in a page printer is eliminated and a format can be arbitrarily designed.

CONSTITUTION: When document format data is transferred from a disk device to a page printer with pi-character codes and the number of characters written on a document format data file, a memory capacity of a page printer is checked (ST3). If a memory is short of capacity, format data of a document having a minimum frequency of use is deleted (ST7). The appropriate document format data and pi-character font data are transferred ST9 from the disk device to the memory of the page printer, as required. In this manner, pi-characters registered in the disk device can be processed without the limination of the capacity of the memory of the page printer.