In this paper, the effect of elevated temperatures (up to 1000 °C) on thermal properties of two similar types of high-performance concrete containing fine ceramic waste and clay shale, respectively are used as a partial replacement of the cement binder is investigated. Samples were prepared in the same manner and both types of concrete contained from 0 to 60 mass% of either replacement. Both replacements were used in our study as a pozzolana active material which can partially replace cement binder and can improve the final properties of concrete. The aim of this paper is to compare the influence of two different pozzolana active materials on selected thermal properties of high-performance concrete at high temperatures up to 1000 °C. The investigation was performed using the differential scanning calorimetry and these results were supplemented by measurement on horizontal dilatometer.