The present invention provides a cartridge life detecting system which detects and manages the life of a cartridge by mounting a memory on a print cartridge comprising at least an image formation member removably mounted on a main body of an image formation apparatus, carrying out operation to obtain information about the life of the cartridge based on contents read from the memory and criterial information of the life of the cartridge, and writing information about the life in the memory, comprises the steps of setting a value corresponding to the life of the cartridge by selecting one among combination of the number of printed sheets and the number of rotations of the image formation member, combination of the number of printed sheets and the number of pixels of image information, and combination of the number of printed sheets, the number of rotations of the image formation member and the number of pixels of image information, storing the value in the memory in advance, and making determination as to the life of the cartridge based on the value.