Green hydrogen is rapidly emerging as a sustainable energy source of global significance. The utilization of water electrolysis for hydrogen production offers environmental advantages and enhances energy security in various sectors, including transportation. However, the substantial challenge lies in effectively storing the hydrogen being produced. To address this, repurposing abandoned gas and oil reservoirs presents a convenient option for establishing underground hydrogen storage (UHS) facilities, capitalizing on the existing infrastructure. These reservoirs possess favorable geological characteristics, stable caprock, and readily available surface and subsurface equipment, making them suitable for UHS operations. The success of UHS is highly dependent on the integrity of injection, production, and blocked wells. Inadequate integrity can result in environmental hazards and inefficient storage practices. The cement sheath encasing the wellbore plays a critical role in preserving well integrity by preventing hydrogen from escaping through cracks, weak areas, or other openings that could lead to uncontrolled emissions or contamination of surrounding formations. Furthermore, stored hydrogen can influence the stability and rheological properties of the cement, adversely impacting the storage process. Consequently, this research involves the experimental exposure of wet cement to hydrogen exposure for varying durations to evaluate the effects on the rheological, mechanical, and chemical properties of the cement. The findings indicate that exposure to hydrogen weakens the cement's compressive strength and density, while simultaneously increasing the viscosity of the cement slurry. XRF analysis reveals the presence of significant amounts of Calcite and Portlandite in each sample, both before and after exposure to hydrogen. XRD results indicate a decrease in the intensity and full width at half-maximum (FWHM) of the calcite peak after exposure to hydrogen. On the contrary, the FWHM and peak intensity of the portlandite phase increased following the exposure process. The FT-IR spectra demonstrate that longer hydrogen exposure times lead to increased water adsorption in the samples. Furthermore, there is a decreasing trend in the peak intensity of the carbonate group with prolonged hydrogen exposure. The XPS study reveals that longer exposure to hydrogen resulted in the formation of more calcium hydroxide phases and the emergence of new carbon-oxygen linkages in the treated samples. These findings suggest that hydrogen and cement undergo chemical reactions.