This study aimed to develop and characterize a heat- polymerized poly(methyl methacrylate) (PMMA) denture base nanocomposite reinforced with hydroxyapatite nanoparticles (HA NPs) and economically synthesized date seed nanoparticles (DS NPs) to enhance its mechanical and tribological properties. Nanocomposites were fabricated with varying concentrations (0, 0.2, 0.4, 0.6, 0.8, and 1.0 wt.%) of HA NPs and DS NPs. The mechanical performance was evaluated through compression testing and Shore D hardness measurements. Tribological properties were assessed using a pin-on-disk tribometer against emery paper, stainless steel and PMMA counterfaces, measuring weight loss, wear rate (Wr), and the coefficient of friction (COF). X-ray diffraction (XRD) was used to characterize the crystallographic structure and structural properties of nanocomposite. Differential scanning calorimetry (DSC) for characterizing the thermal behavior and stability of materials. Morphological analysis of wear tracks was conducted via scanning electron microscopy (SEM). The morphological features and aggregation behavior of the synthesized DS NPs were investigated using transmission electron microscopy (TEM). The findings revealed marked enhancements in the properties relative to unreinforced PMMA. Compressive strength and Shore D hardness increasing by 21.88% and 9.16%, respectively. In addition, the Wr and COF were reduced by 33.76% and 29.88%. SEM observations confirmed that the incorporation of nanoparticles effectively minimized abrasive wear and surface cracking. Among all tested compositions, the 1.0 wt.% filler loading for both nanofiller exhibited the most exceptional performance characteristics.