<p>Currently, nanoparticles are frequently employed in concrete to enhance its diverse characteristics. However, studies typically focus on the effects of these additives in specific conditions, overlooking scenarios such as high temperatures. This research delves into the influence of integrating nano-silica and graphene nano-oxide into concrete, specifically emphasizing their impact on mechanical properties and durability when subjected to elevated temperatures—a distinctive feature of this study. The results show that the addition of 3% nano-silica improves both compressive and splitting tensile strength by 15%, while the inclusion of graphene nano-oxide may have a negative effect on residual mechanical performance after heating. The combination of these additives does not significantly impact durability. Under high heat conditions (900 degrees Celsius), concrete strength decreases by 65%, with a notable drop of up to 80% observed when graphene nano-oxide is present at 0.3%. Water absorption levels increase by 50–80% post-heating, indicating reduced durability. Overall, the findings suggest that the combined use of nano-silica and graphene nano-oxide does not have a positive effect on the mechanical properties or durability of concrete, either before or after exposure to heat.</p>