An information recording medium comprises a user area, and a spare area including a replacement area, wherein the replacement area may be used instead of a defective area in the user area. The user area and the spare area include a plurality of sectors. Each of the plurality of sectors includes a user data area for recording user data, and an attribute data area for recording defect replacement allowance attribute data. The defect replacement allowance attribute data indicates whether recording of the user data has been executed in a state that the execution of a defect replacement process is allowed. In the defect replacement process, the defective area in the user area is replaced with the replacement area in the spare area.