Recently various types of optical discs have been developed and used. Compact Disc Recordable (CD-R) is a disc where enormous amounts of digital data can be recorded and played in currently used CD player or CD-ROM drive. The reflection and absorption rate of the laser beam in the layers of CD-R were numerically calculated. The laser beam energy absorbed in the recording layer is converted to heat, and this is transferred to the neighboring layers. The transient temperature distributions in the layers on recording were obtained numerically using ANSYS software. The written spot in the recording layer was heated far above its decomposition temperature and part of the polycarbonate substrate was heated above its glass transition temperature. After optical recording, the image of the recorded area was obtained by using an atomic forces microscope (AFM). The recording mechanism of CD-R was discussed with these numerical calculations and experimental observations.