To provide an optical disk recording/reproducing apparatus capable of immediately suspending recording if a recording inadequate state occurs after start of recording, confirming the recording state by using an error-correction-code word unit and restarting recording after identifying the write continuation position. A recording starting section (1) instructs a recording gate/recording data creating section (5) to create a recording gate corresponding to a desired volume of data and recording data and to perform recording. If an inadequate-recording-state determining section (2) detects a recording inadequate state, a recording suspending section (3) instructs the recording gate/recording data creating section (5) to suspend outputting the recording gate and the recording data. A SYNC detection section (9) detects a SYNC signal from reproduced data, and a PO-error-correction processing section (11) performs PI-error-correction. A recording-suspended-position determining section (13) determines to what extent the recording has been performed. Depending on the result, a recording restart section (4) issues an instruction to restart recording, and the recording gate/recording data creating section (5) creates again the recording gate and recording data and restarts the recording.