A writable-once optical recording medium such as a BD-WO, and a method and apparatus for managing the writable-once optical recording medium, are provided. According to an embodiment, the method includes recording temporary management information in a temporary defect management area of the recording medium, the temporary management information including disc usage management information indicating a recording or non-recording status of the user area of the each recording layer; and transferring the disc usage management information from the at least one temporary defect management area to the at least one final defect management area of the recording medium, wherein in the recording step, the disc usage management information for each of the recording layers is separately recorded in the temporary defect management area.