To output image information all the time by managing the use situation of expendables in each image forming device and selecting an image forming device which outputs image information so that the replacement time of expendables for each image forming device can not be overlapped based on the use situation of the expendables.

Personal computers PC1 to PC4 and printers PR1 and PR2 are connected onto a network 1, and a network server (print server) 2 which manages the states (use state and situation) of 1st and 2nd expendables in the printers PR1 and PR2 is connected to the network 1. When an output command of image information is issued, because the server 2 is connected onto the network 1, the server 2 selects the printer PR1 and PR2 outputting the image information so that the replacement time of the 1st expendables for each printer PR1 and PR2 can not be overlapped based on the use situations of the 1st and 2nd expendables.