This work emphasizes the importance of utilizing cuttlebone waste as a sustainable solution for waste management and the development of antimicrobial materials by incorporating it as a supporting phase for polyaniline (PANI) to form a nanocomposite. The three prepared materials were fully characterized using various techniques, including FTIR, XRD, SEM, EDX for elemental analysis, Brunauer-Emmett-Teller (BET) surface area measurements, particle size distribution analysis, and zeta potential measurements. The study focuses on the development of novel molecules with potential antibacterial and antifungal activity against clinical pathogens responsible for infectious diseases. The antibacterial and antifungal activities of the polyaniline/cuttlebone (PANI/CB) composite were evaluated using methods such as minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and disk diffusion for bacterial samples, as well as MIC, minimum fungicidal concentration (MFC), antifungal percentage, and disk diffusion for fungal samples. Notably, the PANI/CB composite exhibited a distinct crystallite size and characteristic XRD pattern, along with a significant BET surface area, demonstrating strong antimicrobial properties. Cuttlebone not only serves as a bioactive agent but also acts as a sustainable support to enhance the properties of polyaniline, forming a nanocomposite with a low MIC range (8-66 μg mL