Abstract—Mechanical properties of concrete decrease when subjected to high temperatures. It is desired to reduce concrete surface temperature when it is subjected to high temperature. In this study, different proportions of glass beads (10%, 20%, 30%) and blast furnace slag (+10%, +20%, -10%, -20%) were added into C30/37 strength class concrete samples to reduce the concrete surface temperature when it is subjected to 3000°C flame for a short time. Mechanical properties of concrete samples were also measured. It was determined that lower surface temperatures can be obtained by regulating concrete mixture with optimum proportions of glass beads and blast furnace slag when the concrete is subjected to high temperature. In this study, the easy, cheap and time consuming test is also presented to find the better concrete mixture when subjected to high temperature.