Hydrogen is increasingly recognized as a pivotal clean energy carrier with immense potential to transform global energy systems. While industrial hydrogen production often involves processes that emit carbon dioxide, such as steam methane reforming, the exploration of natural hydrogen represents a carbon–neutral alternative with significant advantages. Natural hydrogen, generated through geochemical processes like serpentinization, radiolysis, and water–rock interactions, offers a stable and renewable energy resource stored within the Earth’s crust. This review delves into the geological and geochemical factors influencing the formation and accumulation of natural hydrogen, with particular emphasis on key geological environments such as ophiolites, Precambrian formations, and fault systems. Additionally, it examines advanced exploration techniques, including geophysical surveys, isotopic analyses, and borehole logging, which are instrumental in identifying and quantifying subsurface hydrogen reservoirs. The findings underscore the significance of integrating geological, geochemical, and geophysical data for accurate mapping and efficient exploration of natural hydrogen sources. This study highlights the potential of natural hydrogen as a sustainable, carbon-free energy resource, offering a pathway to a cleaner energy future while addressing the growing demand for renewable energy solutions. We also examine geological structures, rock and soil properties, and the mechanical stability of hydrogen-bearing formations. Future directions, technological innovations, and the challenges of geotechnical risk management in hydrogen exploration are also discussed.

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