This study presents a comparative analysis of the effectiveness of two industrial waste products, Granulated Blast Furnace Slag (GBFS) and Steel Slag (SS), in enhancing the engineering properties of black cotton soil. Various percentages (5%, 10%, 15%, and 20% by weight of soil) of GBFS and SS were replaced in the soil, and a series of tests, including consistency limits, standard proctor, and strength characteristics tests (unconfined compressive strength (UCS) and California bearing ratio (CBR)) were conducted. The results revealed that the optimum percentage of GBFS exhibited superior strength characteristics compared to the optimum percentage of SS. This finding suggests that GBFS may be more effective in improving the engineering properties of black cotton soil compared to SS. This study stands out as a pioneering endeavor, being one of the first to conduct a comparison between Granulated Blast Furnace Slag (GBFS) and Steel Slag (SS) on equal footing, thus accentuating the novelty of the research.