<p>The growing pressure on freshwater resources, driven by rapid population growth, climate change and increasing agricultural demands, has made optimizing water use a critical priority. Crop Water Productivity (CWP), a measure of crop yield per unit of water consumed, is a key metric for assessing agricultural water use efficiency and guiding sustainable agricultural management. Recently, remote sensing has become indispensable for CWP estimation by providing spatially explicit, multi-temporal and cost-effective observations. However, existing studies vary widely in terms of data sources, modeling techniques, and validation approaches, which leads to inconsistencies and challenges in comparing and/or operationalizing remote sensing based CWP estimates. To address these limitations, this systematic review synthesizes recent research evidence from 93 peer-reviewed studies published between 2020 and 2025 to critically examine conceptual frameworks and methodological approaches applied in the estimation of crop yield and actual evapotranspiration (ETa), which are the two fundamental components in CWP estimation. The study offers a consolidated and up-to-date reference for researchers and practitioners aiming to advance remote-sensing-based CWP assessment and design more reliable, scalable, and operational water productivity monitoring systems. The novelty of this review thus, lies in its comprehensive cross-comparison of ETa and yield estimation methods, its integration of multisource insights and its clear identification of opportunities for methodological enhancements. Future research directions are recommended, including improving ETa and yield modeling, expanding multisource integration and strengthening ground-based validation protocols.</p>