To provide a font caching method, which effectively functions even under the condition that the throughput of a CPU is low and, at the same time, any dead RAM is scarcely present.

In a font caching method, in which a cache area for temporarily storing font data, fixed number of block areas having fixed lengths as a font cache memory are formed in a RAM. When the output request of fonts is issued, the font block areas are directly retrieved at steps S13-S18. When an output- requested font is present in the area, the data of the font are used at a step S16. When the output-requested font does not present in the cache area, font data are expanded into bit map data at a step S19 so as to store the expanded data in a block area having the fixed length at steps S20-S24, when the expanded data can be stored and a dead area is present in the areas.