The present experiment aims at investigating the medium-term effect of sewage sludge as an organic amendment to a degraded, saline soil in Central West Tunisia. The field research plot measures 4.22 ha, and 5 t/ha of sewage sludge dry powder was applied. Soil and leaves samples were collected after six months of application and two years later to assess the immediate and medium-term effects of Sludge on soil quality, from the first layer of the soil horizon (0-30 cm). Before the application, soil pH was neutral at about 8.0; since then, it has slipped towards 7.6. Electrical conductivity was already high (roughly 17.1 mS/cm) and climbed to 25.1 mS/cm in 2023. Organic matter rates were under 1%, later increased to nearly 2.1%, noticeably boosting fertility and soil structure. Phosphorus increased from 6.67 to 57.10 ppm. Water-holding capacity also improved, elevating from about 50% to 53-66% in 2023 and settling at 56.4% by 2025, so the soil keeps moisture longer. The mean concentrations of the heavy metals in the soil were in the following order: Fe > Mn > Pb > Zn > Ni > Cd > Cu. While the leaves were in the order of Fe > Ni > Mn > Zn > Pb > Cu > Cd. However, their post-application concentrations were well within limits and not harmful. The 2025 data indicate a stabilization, notably in Organic matter. Heavy metals in the soil showed stabilization or slight decrease, due to natural soil processes such as leaching, adsorption, or plant uptake. Continued monitoring is important in assessing bioavailability and mobility over time to ensure the sustainable use of Sludge in agriculture. [GRAPHICS]