An image forming system includes a PDL job receiving unit for receiving a PDL job generated by use of a page description language, a print image forming unit for interpreting the PDL job and forming a print image, a compression unit for compressing the print image, a storage unit for storing the compressed image formed by the compression unit, a hybrid print demand receiving unit for receiving a hybrid print demand that demands the compressed image in the storage unit to be hybrid-printed, an expansion unit for expanding the compressed image, and a transmitting unit for transmitting the expanded image formed by the expansion unit to a printer engine. The image forming system further includes a control unit for, when judging that the PDL job receiving unit receives the PDL job, forming the print image from the PDL job, compressing the print image and storing the compressed image in the storage unit, and when judging that the hybrid print demand receiving unit receives the hybrid print demand, expanding the compressed image in the storage unit by use of the expansion unit in response to the hybrid print demand, and sending the expanded image to the printer engine.