Starch-based bio plastics, due to their abundance, recyclability, and biodegradability, offer a promising alternative to conventional petrochemical-based plastics. Additives significantly influences the functionality of bioplastics. This study investigates the effects of polyvinyl alcohol (PVA) and carboxymethyl cellulose (CMC) at varying concentrations on banana starch-based bioplastic films, using glycerol as a plasticizer. CMC-based films exhibited higher L* values and thickness (0.51-1.55 mm) compared to PVA films. Due to hydrophilicity, CMC films demonstrated 2-3 times greater solubility (17-23 %) and water absorption (75.29 %). Moisture-rich films, C3 and PC2:1, showed the highest WVTR values of 25.73 and 24.10 g/m