Abstract— It has significant potential to strengthen carboxymethyl cellulose/gelatin nanocomposite with cellulose nanocrystals from plantain stems for the production of bioplastics. Alkaline pretreatment and acid hydrolysis were used to extract cellulose nanocrystals from plantain stem. Films made of carboxymethyl cellulose and gelatin were strengthened using cellulose nanocrystals made from plantain stem fiber. SEM, thermogravimetric analysis (TGA), and water vapour permeability (WVP) were used to characterize the synthetic bioplastic's physical properties. The environmental deterioration of the bioplastic samples was observed over time at regular intervals in soil that was taken from a waste landfill. The results showed that the water vapour permeability of the investigated films was decreased by the addition of CNC from 2.45 x 10-6g/m x h x Pa to 1.73 x 10-6g/m x h x Pa. Additionally, it was discovered that unreinforced films degraded by 0.2% after 35 days, whereas 5wt% and 10wt% CNC reinforced films lost weight as a result of biodegradation by 0.1% and 0.18%, respectively. Overall, the interconnected carboxymethyl cellulose/gelatin bolstered CNC nanocomposite film for making plastics increased the heat and water vapour permeability of the packaging film, which offers the chances of their packaging application.