A print document processing system includes a cache apparatus and plural data processing apparatuses. Each data processing apparatus includes an image data creating unit and a reservation request transmission unit. The cache apparatus includes a cache memory, a memory, and an area reservation unit. The image data creating unit creates image data for each document element of print document data. The memory stores use condition information and cache priority of the document element for each document element. Upon receipt of a reservation request for reserving a storage area for image data of a first document element from a data processing apparatus, the area reservation unit reserves the storage area by selecting a second document element, which has a lower cache priority than the first document element and which is currently being used by any of the data processing apparatuses, as a document element to be evicted from the cache memory.