This study investigates the pozzolanic efficacy of waste ceramic powder as a partial binder substitute in Portland cement concrete, evaluated at mass replacement levels of 0%, 5%, 10%, and 20%. The primary objective is to advance sustainable concrete technology while mitigating the environmental footprint associated with clinker production and industrial solid waste disposal. The experimental program involved casting cubic specimens subjected to an extended curing regime consisting of 28 days of water immersion followed by 28 days of laboratory air curing. Compressive strength and dry density parameters were systematically determined at 58 days. The mechanical evaluation demonstrated resilient structural behavior; while the control mixture attained a peak compressive strength of 56.67 MPa, the ceramic-incorporated mixtures retained high performance levels, yielding 54.17 MPa at 5% and 53.30 MPa at 20% replacement—representing a marginal strength loss capped at 5.9%. Furthermore, dry density values exhibited consistent structural stability across all substitution ratios. These findings are attributed to the delayed pozzolanic reactivity of fine ceramic particulates, which react with hydration-derived calcium hydroxide to form supplementary calcium silicate hydrate (C-S-H) gels. Overall, the results confirm that incorporating up to 20% waste ceramic powder offers a viable, eco-friendly cementitious alternative without compromising structural integrity................... Keywords:................ Waste Ceramic Powder, Pozzolanic Efficacy, Sustainable Concrete, Compressive Strength, Extended Curing.