Peat soils are soils with low load-bearing, high compressibility and very saturated in water, which requires stabilization before their use as a foundation layer. This study examines the effect of the addition of Evocrete additives and an Evocrete-lime combination on improving the physical and mechanical properties of fibrous peat soils. Analyses include water content, density, organic matter content, ash content, fiber content, pH, as well as mechanical tests such as compaction test, simple compressive strength test (UCS), and UU triaxial test. Different proportions of Evocrete were used, from 5% to 25%, as well as a combination of 25% Evocrete and lime, at percentages ranging from 5% to 25%. The results showed that the addition of Evocrete increased dry density, shear strength, and compressive strength. The combination of Evocrete and lime allowed for a more significant increase, particularly for an Evocrete content of 25% and a lime content of 15% to 20%. In conclusion, Evocrete effectively improves the mechanical properties of peat soils and optimal performance is achieved through the Evocrete-lime combination.