According to one embodiment, there is provided a method of managing an EUV exposure mask to manage a cleaning period of the EUV exposure mask set in an exposure apparatus, including obtaining mark profile signals corresponding to two different directions of an alignment mark provided on the mask by irradiating the mark with EUV light and detecting light reflected by the mask, measuring dimensions of the mark in the two different directions from the obtained mark profile signals, calculating a difference between the measured dimensions in the two different directions, and determining the cleaning period of the mask based on the calculated difference.