To provide a device management apparatus capable of surely saving and reading out the use amount of a device with a small number of non-volatile memories without exceeding a write frequency limit of the non-volatile memory and without the need of configuration for detecting the off-state of a power supply.

This device management apparatus includes a measuring means 11 for measuring the use amount of the device or a unit connected to the device, and a non-volatile memory 12 for saving the use amount and limiting the write frequency in every area. The apparatus further includes an area select means 13 for selecting two or more of areas having an integral multiple of size determining the limited write frequency in the non-volatile memory in every user amount, an arithmetic means 14 for obtaining a value saved in each area in every area selected by the area select means, a comparing means 15 for comparing the value obtained by the arithmetic means with the value not saved in the area, and a control means for controlling to save the value obtained by the arithmetic means in the concerned area if the values are different, and not to save the value if the values are not different.