This paper presents the study conducted on the utilization and effects of various particle sizes of Waste Glass Powder (WGP) as a partial replacement of cement in concrete. By employing WGP as a cement substitute, the physical and mechanical characteristics, workability, and compressive strength of concrete were assessed. The glass has been sieved from the #200 sieve which has a size of 74 µm and also sieved from the #325 sieve which has a size of 44 µm for a partial replacement of cement. To compare the WGP-replaced concrete's properties to reference specimens with no replacement at all, 20% of the Portland cement in the concrete was replaced with WGP. The control samples were created following the IS-10262-2009 standard to reflect a goal of 30 Mpa, and cylinder specimens were cast, cured, and evaluated for workability and compressive strength at 7, 14, 21, and 28 days after its casting. In conclusion, when the WGP particles are smaller, concrete becomes more workable and has a higher compressive strength than concrete with bigger particle sizes of WGP and control samples with no replacement. The findings of this study led to the conclusion that WGP's cementitious properties are acquired by its finer particles.