We propose a novel application of optical coherence tomography (OCT) to monitor pit formation in laser-irradiated optical storage materials. A multilayer optical storage recordable compact disk is composed of multiple layers, each of different structure. The disks were irradiated with a Q-Switched Nd:YAG laser with an energy of 373 mJ. Post-irradiated disks were evaluated by using OCT, and the images were compared with those obtained by using optical microscopy. Our results indicate that OCT can be a useful instrument for investigating pit formation in multilayer optical storage disks and might also provide information on ways to optimize optical memory technology.