This study experimentally investigated the partial replacement of m-sand (natural sand) with steel slag as fine aggregate in concrete. Various concrete mixes were prepared by replacing m-sand with 10%, 20%, 30%, and 40% steel slag by volume. The compressive strength, tensile strength, and flexural strength of the concrete cubes, cylinders, and beams were tested and compared to a conventional concrete mix without steel slag. The results showed that replacing up to 30% of m-sand with steel slag did not negatively impact the strength of the concrete and can be a viable way to utilize an industrial waste product in construction.