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 prepared using an injection molding process, with the final composition containing 20 wt% NaOH-treated jute fiber and varying amounts of nano SiC (0, 4, 8, and 12 wt%). The results indicate that the addition of NaOH-treated jute fiber and nano SiC significantly enhances the tensile and flexural strength and energy absorption behavior of the LDPE composites. The composite with 20 wt% NaOH-treated jute fiber and 12 wt% SiC exhibited the highest tensile and flexural strengths of 22.5 ± 0.5 MPa and 18.5 ± 0.7 MPa, respectively, and improved energy absorption of 24 ± 1 J compared to the unmodified LDPE matrix. The study highlights the potential of this hybrid nanocomposite for applications requiring high mechanical performance and recyclability.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 prepared using an injection molding process, with the final composition containing 20 wt% NaOH-treated jute fiber and varying amounts of nano SiC (0, 4, 8, and 12 wt%). The results indicate that the addition of NaOH-treated jute fiber and nano SiC significantly enhances the tensile and flexural strength and energy absorption behavior of the LDPE composites. The composite with 20 wt% NaOH-treated jute fiber and 12 wt% SiC exhibited the highest tensile and flexural strengths of 22.5 ± 0.5 MPa and 18.5 ± 0.7 MPa, respectively, and improved energy absorption of 24 ± 1 J compared to the unmodified LDPE matrix. The study highlights the potential of this hybrid nanocomposite for applications requiring high mechanical performance and recyclability.