This investigation was carried out to study the effects of replacement percentage and fineness of ground granulated blast-furnace slag (GGBFS) on the autogenous shrinkage of high-performance concrete. All the mixtures had the same water-cementitious materials ratio (w/cm = 0.30) and the same volume of binder at 31 % of the total volume of concrete. The 91-day compressive strengths of all the concretes were above 80 MPa. Test results revealed that the 50% GGBFS concrete had the highest compressive strength at 91 days and the highest autogenous shrinkage. It was also found that concrete specimens containing finer GGBFS particles showed faster compressive strength development and greater autogenous shrinkage strains.