Abstract: Microstructure and strength characteristic of Iss stabilized silty sand and sandy silty soil with low liquid limit are studied through chemical analysis, unconfined compression test and analysis using scanning electron microscopy.The research result shows that mixed with ISS the soil is easy to compact and density of it increases,therefore the strength of soil increase.Fibrous mineral can grow to fill the pore between soil grain when adding proper quantity of cement, accord-ingly the strength of stabilized soil and its ability of resistance to deformation increase conspicuously.