The boron compounds have been widely used as additives in the production of cement and concrete to enhance their engineering properties. In this study, three series of concrete specimens were produced using B2O3 additive materials, boron modified active belite cement and Portland cement. After 28 days of curing period the specimens were exposed to temperatures of 250, 500 and 750 degrees C. Mass loss and compressive strength were determined and recorded after the specimens were cooled to room temperature. It was concluded that the effect of the boron becomes more apparent at high temperatures.