Volume 6 Article informations Composting and lixiviation, case study in Médenine-Tunisia Kaouther Ardhaoui a,* , Fatima Bellali b , Mohamed Moussa c Abstract Composting is an important method for the recycling of organic waste collected from agricultural trashes or kitchen scraps. Adding compost to sandy soils improves the water holding capacity, and makes clay soils easier to work and plant. Through adding organic matter to the soil, compost can help to improve plant growth and health. This study was about the preparation of compost from organic domestic leftovers and garden trimming wastes. Different physicochemical characteristics of compost were determined during and after realization. In addition, incubated compost with rainwater were studied, in order to simulate the behavior of this product in the environment and to understand the effect of lixiviated water. The kinetic evolution of various physicochemical characteristics was followed for a period of several weeks. In fact, by incubating compost in rainwater, it liberates minerals likes calcium, magnesium and phosphates. Key words: Composting, Kinetic, lixiviation, Tunisia.