This chapter investigates PFAS and PFOS contamination of soil and groundwater system and discusses the potential remedial strategies. Per- and polyfluoroalkyl substances (PFAS), including perfluorooctane sulfonate (PFOS), are persistent organic pollutants that pose severe threats to soil, groundwater, and human health. Their exceptional stability, due to strong carbon–fluorine bonds, allows them to resist natural degradation processes, leading to long-term environmental persistence. PFAS enter soil and groundwater systems through industrial discharges, landfill leachates, biosolid applications, and surface runoff. Short-chain PFAS, such as PFBA and PFBS, are more mobile and easily reach groundwater, while long-chain compounds like PFOS and PFOA tend to sorb strongly to soil and organic matter. Soil characteristics, including pH, texture, and organic carbon, significantly influence PFAS adsorption, retention, and migration. Within plants, PFAS are absorbed primarily through roots, with short-chain compounds translocating more readily to aerial parts, creating indirect exposure risks through food consumption. These processes collectively impact groundwater recharge and water quality, especially in areas near industrial or agricultural sources. Conventional remediation methods such as air stripping, biodegradation, and pump-and-treat are largely ineffective due to PFAS’s chemical resilience. Alternative strategies, including activated carbon adsorption, ion exchange, soil washing, and emerging technologies like plasma treatment and electrochemical oxidation, are under investigation, though none yet provide a sustainable solution. Addressing PFAS contamination requires integrated, site-specific approaches involving long-term monitoring, modelling, and policy coordination. Enhanced understanding of PFAS fate, transport, and ecological effects, along with regulatory enforcement and stakeholder collaboration, is essential to mitigate ongoing risks. Ultimately, the PFAS issue highlights the urgent need for interdisciplinary research and innovative technologies to protect soil, water, and public health.