Photoresponsive nanomaterials have emerged as a transformative class of advanced functional materials for high-speed optical switching and next-generation photonic technologies. These nanomaterials exhibit rapid and reversible changes in their optical, electronic, and structural properties upon exposure to external light stimuli, enabling ultrafast manipulation of optical signals. The present study investigates the structural characteristics, photoresponsive mechanisms, and optical switching capabilities of various nanomaterials including graphene derivatives, metal halide perovskites, quantum dots, plasmonic nanoparticles, and photochromic nanostructures. The study focuses on their applications in all-optical switching, photonic communication systems, optical memory devices, and integrated nanophotonic circuits. The findings indicate that photoresponsive nanomaterials demonstrate exceptional nonlinear optical behaviour, ultrafast carrier dynamics, tunable refractive indices, and strong light–matter interaction, making them highly suitable for high-speed optical switching applications. Enhanced switching speed, low power consumption, high optical contrast, and nanoscale integration capability were identified as major advantages of these materials compared to conventional optical switching systems. The study further highlights the importance of plasmonic enhancement, quantum confinement effects, and nanostructural engineering in improving optical response efficiency and switching performance. Despite challenges related to fabrication complexity, material stability, and optical losses, photoresponsive nanomaterials represent a highly promising platform for future ultrafast photonic communication and optical computing technologies.