Aim: The study aimed to fabricate and evaluate the impact strength and flexural strength of heat-cure polymethyl methacrylate (PMMA) denture base resin, reinforced with human hair and spider silk fibers. Materials and methods: Specimens were made by incorporating human hair fibers and spider silk fibers into the PMMA (by compression molding technique) in varying quantities. The impact strength and flexural strength were measured using standard equipment and compared with control specimens (without reinforcement). A scanning electron microscope (SEM) was used to study the fractured surface of the fiber-reinforced composites. Results: There was a significant increase in impact strength and flexural strength of the reinforced specimens up to a certain optimum level of fiber reinforcement compared to the control specimen. Conclusion: The human hair and spider silk fiber-reinforced PMMA showed a significant increase in mechanical properties. The present investigation proved that the reinforcement of biopolymers such as hair and spider silk could improve the mechanical properties of PMMA acrylic resin, which is widely used as a denture base material for the fabrication of record bases, special trays, etc. Clinical significance: Reinforcement of biopolymers such as hair and spider silk can be incorporated into PMMA acrylic resin to improve its mechanical properties. © 2024 Elsevier B.V., All rights reserved.