Abstract This study aims to investigate the structural, thermal, and spectral characteristics along with ultra-violet (UV) absorption of various marine benthos exoskeletons, such as various species of crabs (Portunus sanguinolentus, Portunus pelagicus, Charybdis feriata) and mantis shrimp (Oratosquilla oratoria). Their unique properties and ability to survive in harsh oceanic environments make them interesting research subjects. This research utilized powder X-ray diffraction (XRD) analysis to determine the crystal structure of the benthic varieties. The sample surface was analysed using high-resolution micrographs obtained from field-emission scanning electron microscopy (FESEM) identified the presence of chitin and calcite in the marine benthos, which was further confirmed by differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR). The optical characteristics were investigated using UV-visible spectroscopy. The proximate analysis revealed high protein content in the mantis shrimp exoskeleton compared to other crab species, revealing its excellent UV-absorption characteristics. Overall, this research has the potential to broaden our understanding of marine organisms, which can have potential applications in biotechnology and materials science to develop nature-inspired innovative materials sustainably.