This study investigates the mechanical behavior of low-density polyethylene (LDPE) hybrid nanocomposites reinforced with NaOH-treated jute fiber and silicon carbide (SiC) nanoparticles. The composite was fabricated using an injection molding process, with 20 wt% NaOH-treated jute fiber and 0, 4, 8, or 12 wt% SiC nanoparticles. The results showed that the addition of SiC nanoparticles significantly improved the tensile and flexural strength, as well as energy absorption capacity of the composite. The composite with 12 wt% SiC nanoparticles exhibited the highest tensile strength of 22.5 ± 0.5 MPa and flexural strength of 18.5 ± 0.7 MPa, along with improved energy absorption of 24 ± 1 J. The study highlights the effectiveness of combining NaOH-treated jute fiber with SiC nanoparticles in enhancing the mechanical properties of LDPE composites. The results indicate that the hybrid nanocomposite with 20 wt% NaOH-treated jute fiber and 12 wt% SiC nanoparticles offers superior mechanical performance compared to the pure LDPE matrix. The study also emphasizes the importance of using natural fibers and nanoparticles in polymer composites to achieve better mechanical and thermal properties. The injection molding process was found to be suitable for producing complex shapes and is a viable method for fabricating LDPE composites. The study concludes that the combination of NaOH-treated jute fiber and SiC nanoparticles can significantly enhance the mechanical properties of LDPE composites, making them suitable for various industrial applications.This study investigates the mechanical behavior of low-density polyethylene (LDPE) hybrid nanocomposites reinforced with NaOH-treated jute fiber and silicon carbide (SiC) nanoparticles. The composite was fabricated using an injection molding process, with 20 wt% NaOH-treated jute fiber and 0, 4, 8, or 12 wt% SiC nanoparticles. The results showed that the addition of SiC nanoparticles significantly improved the tensile and flexural strength, as well as energy absorption capacity of the composite. The composite with 12 wt% SiC nanoparticles exhibited the highest tensile strength of 22.5 ± 0.5 MPa and flexural strength of 18.5 ± 0.7 MPa, along with improved energy absorption of 24 ± 1 J. The study highlights the effectiveness of combining NaOH-treated jute fiber with SiC nanoparticles in enhancing the mechanical properties of LDPE composites. The results indicate that the hybrid nanocomposite with 20 wt% NaOH-treated jute fiber and 12 wt% SiC nanoparticles offers superior mechanical performance compared to the pure LDPE matrix. The study also emphasizes the importance of using natural fibers and nanoparticles in polymer composites to achieve better mechanical and thermal properties. The injection molding process was found to be suitable for producing complex shapes and is a viable method for fabricating LDPE composites. The study concludes that the combination of NaOH-treated jute fiber and SiC nanoparticles can significantly enhance the mechanical properties of LDPE composites, making them suitable for various industrial applications.