A method and apparatus for recording or reproducing data are discussed. According to an embodiment, the invention is directed to a method for recording data onto a recording medium having a recording layer, the recording layer including an inner area, a data area and an outer area, the data area having a user data area and a spare area, the user data area consisting of a plurality of clusters, the method comprising steps of: (a) recording a first data block having a temporary defect list for managing a defective area of the data area onto a temporary defect management area allocated in the inner area or the spare area; and (b) recording a second data block having a space bitmap onto the temporary defect management area.