Groundwater is a vital natural resource for sustaining human and ecosystem needs. The advent of Geographic Information Systems (GIS) has revolutionized groundwater research by providing a spatial framework for data integration, analysis, and visualization. This paper provides a comprehensive review of the applications of GIS in groundwater research. The review covers the use of GIS in groundwater exploration, monitoring, assessment, management, and modelling. Additionally, the paper highlights the advantages and limitations of using GIS in groundwater research and the future research directions.