Landfill liner is a containment system used between landfill waste and the ground soil to prevent the migration of leachate into the soil and groundwater. Clay is typically used as a liner in the landfill barrier system due to efficiency and low permeability. Over the last decade, different types of binders such as cement, fly ash, and slag have been used with clay to improve the mechanical characteristics and reduce hydraulic conductivity of natural clay liners. This study introduced a new sustainable technique where treated dune sand mixed with alkali activated binder (AAB) made with fly ash (FA), ground-granulated blast-furnace slag (GGBFS), and alkali activated solutions are used as a landfill liner system, due to the unavailability of natural clay in most countries. Therefore, lab-scale compacted specimens with different mixing ratios of AABs treated desert sand were prepared and cured for 7 days to conduct a series of compressive strength. The results showed that the 20% binder mixed with 30% FA, 70% slag, and alkali solution of 0.5 have a high compressive strength with 12 MPa compared with other mixing ratios. However, a 10% binder with same precursors ratio of FA and slag has shown a less strength regardless of alkali solution with around 3 MPa. Finally, all mixing ratios have shown that the strength met the requirements of landfill liner system which were greater than 200 kPa.