Recent consideration has been given to use of GGBFS as separate cementitious material mixed along with Portland cement in production of concrete. Problems are frequently encountered in producing good-quality concrete specially slag cement concrete in hot climates.Curing problems are exaggerated when concreting in hot weather, as a result of both higher concrete temperatures and increased rate of evaporation from the fresh mix. The disadvantage of GGBFS concretes is that they proved to be more sensitive to poor curing than OPC Therefore, special care must be taken when using this type of concrete, especially on site, where the working conditions and the application of curing are not as easy to control as in the laboratory concrete. The purpose of this paper is investigation and evaluation strength loss in slag cement concrete in poor curing situation. To carry out this aim, 72 cube specimens with three different proportion of slag are made and cured in two different conditions. And result of compressive tests compared together to determine susceptibility of GGBFS concrete in hot-dry condition.