Background: Denture polymers may be strengthened by modifications of material itself, or by incorporating various reinforcements into the polymer material that enhance the flexural strength. Objectives: To evaluate and compare the flexural strength and fracture toughness of heat activated PMMA resin and heat activated PMMA resin reinforced with E glass fibers. Materials and Methods: A total of 40 specimens were prepared according to the ISO specification (65 × 10 × 3 mm), 20 specimens were reinforced with E glass fibers considered as test samples. They were stored in distilled water bath at 37°C for 48 hours before testing. The flexural strength and the fracture toughness were evaluated using universal testing machine at a cross-head speed of 1 mm/min. Results: Data were analyzed using one sample Kolmogorov-Smirnoff test (Normality test) and t test for the flexural strength and fracture toughness. Conclusion: The flexural strength of heat activated PMMA resin reinforced with E–glass fibers were statistically significant compared to the control group.