Abstract This study explores the influence of olive waste ash (OWA) on the performance of concrete exposed to elevated temperatures in the range from 400 to 600 °C. The performance of concrete to elevated temperature was evaluated using compressive strength and electrical charge of concrete. Three OWA levels were used in the study: 7%, 15%, and 22% by weight of cement. The other experimental parameters investigated in the study were elevated temperature (400 and 600 °C), aggregate type (crushed basalt and volcanic tuff), w/c ratio (0.5 and 0.7), and air content (non-air and air entrained). After the initial moist curing period of 90 days, concrete specimens were exposed to elevated temperatures for a period of 2 h using an electric furnace. The study showed that the performance of OWA concrete to elevated temperatures is higher than that of the control concrete. Additionally, the performance of OWA concrete to elevated temperature increased when the OWA content was increased. The resistance of OWA concrete containing tuff aggregate to elevated temperatures was observed higher compared to OWA concrete containing basalt aggregate. The OWA concrete at w/c ratio of 0.5 was found to be more resistant to elevated temperatures than that of OWA concrete at w/c ratio of 0.7. The performance of the air entrained OWA concrete to elevated temperature was observed higher compared to the non-air entrained OWA concrete.