Self-consolidating concrete (SCC) is a highly flowable yet stable concrete. As high flowability and stability are contradictory properties, SCC is highly sensitive to material type and proportion. An important ingredient of SCC is aggregate, as it occupies 60 to 70% of the concrete’s volume. Therefore, it is essential to study how aggregate characteristics affect the flowability and stability of a SCC mix. This investigation focused on the effect of fine aggregate grading on the performance of fresh SCC. The results indicate that to obtain a high-quality SCC product, aggregates should have a certain maximum size and distribution. However, the effect of poor aggregate grading may be alleviated by proper combination of fine and coarse aggregates. The paper also presents a case study on the development of high strength SCC made with poorly graded fine and coarse aggregates. In this project, the total aggregate grading was influenced by adjusting the sand-aggregate ratio.