<p>The growing volume of construction and demolition waste and the high carbon footprint of cement production have driven interest in waste-derived materials for sustainable concrete. This study presents a critical systematic review of the use of gypsum waste powder (GWP) and ceramic waste powder (CWP) as partial cement replacements, focusing on material mechanisms, performance limits, durability behaviour and sustainability trade-offs. The review follows PRISMA 2020 guidelines, and peer-reviewed studies published between 2015 and 2025 were systematically screened and synthesized. The review indicates that CWP exhibits a broader and more reliable performance window than GWP, attributed to its silica-rich composition, pozzolanic reactivity and microfilling effect. Cement replacement levels of approximately 10–20% CWP are consistently associated with improved compressive and flexural strength, reduced chloride penetration and enhanced durability under controlled curing conditions, whereas higher replacement levels require blending with reactive supplementary cementitious materials. In contrast, GWP demonstrates a narrower and exposure-sensitive applicability, with effective replacement typically limited to 10–15% due to sulphate-related risks affecting setting behaviour and long-term durability. From a sustainability perspective, partial cement replacement using GWP and CWP can reduce embodied CO₂ emissions by approximately 7–10% per 10% cement substitution, although net benefits depend strongly on processing energy, transportation distance and durability performance. Overall, this review establishes clear performance thresholds, failure mechanisms and applicability boundaries for GWP and CWP, providing decision-oriented guidance for sustainable concrete design and identifying key research needs related to durability, standardization and life cycle assessment.</p>