The Abbay BasinAbbay Basin is one of the hydrologically data-scarce basins in EthiopiaEthiopia. However, hydrological information and model simulation outputs require sufficient and near real-time datasets to evidence-based decision about the management of water resourcesWater resources. Earth observationEarth observation (EO) applications is advancing in large basin-level hydrological planningPlanning and development by offering data and information for spatial-based best decision support services and systems. Unfortunately, the application of EO for water resourceWater resources management and development remains a major limitation for many developing countries. Subsequently, EthiopiaEthiopia has not been fully utilizing this opportunity and many impediments remain a critical challenge for EO data application for the water resourceWater resources management and development sector. Therefore, this chapter aimed to explore the status of EO product applications for water monitoring and management efforts in the Abbay BasinAbbay Basin. The application of EO has increased from time to time and EO products could contribute greatly to efficient and effective use of hydrological parametersHydrological parameters and information retrieval, and facilitate the improved decision-making process in the water sector for long-term development in the basin. Specifically, satellite datasets such as remote sensingRemote sensing; meteorological satellites, and global navigation satellite systems (GNSS) show a decisive role in obtaining the spatiotemporal dynamics information and quantitative measurements of the different hydrological parametersHydrological parameters such as the extents of surface water bodies; suspended minerals; bathymetric mapping; land and water surface temperature; precipitationPrecipitation; aerosols; clouds and water vapour as well as dam safety monitoring in the Abbay BasinAbbay Basin. After introducing the status of EO product application in water-related issues, the paper presented the status of EO applications in hydrological parameterHydrological parameters retrieval as well as input for hydrological simulation models and possible remedial suggestions essential to building capacity for EO application for water resourceWater resources monitoring and development in the Abbay BasinAbbay Basin.