After a series of chemical treatments and physical operations, the hides are finally turned into leathers. Nowadays, filling is one of the most important processes in leather manufacture, the filled leather has good performances such as fullness, flexible. According to the different ways of operation, the filling methods are generally divided into wet filling and dry filling. Most commonly used fillers are polyurethane resins and acrylic resins for dry filling. However, so few reports have focused on wet filling with polysaccharide macromolecules. In this work, soluble soybean polysaccharide (SSPS) was applied on leather wet filling. SSPS is good in emulsification, and stable emulsion may be formed with the addition of SSPS in fatliquoring agents. Therefore, wet-blue leather was used as raw materials, then retanned and neutralized, fatliquoring and filling with SSPS were carried out at the same time, with different amounts of SSPS, i.e., 1%, 3%, 5%,7% in weight. Finally, leather samples were dried at room temperature. The effect of SSPS amounts on the thickness, air permeability and water vapor permeability of the crust leather were studied. Also, the tensile property of the leathers filled with SSPS were analyzed. The results indicated that with increasing the amounts of SSPS, the thickness and the water vapor permeability of the leathers increases, while the air permeability decreases. The maximum stress-strain capacity of leathers decreases with increasing the SSPS amount. At the SSPS amount of 3%, the leather is good in softness, as well as in physical and mechanical properties. © 2019 VGCT.