Abstract: The CaCO3-filled SF/PVA blend films were prepared by blending solution with CaCO3 treated with titanate coupling agent. The effects of titanate coupling agent on mechanical properties and stability of wet of CaCO3-filled blend films were discussed. The results showed that when the content of titanate coupling agent was 0.5%, it had good membrane formation property, the improving of the tensile strength, elongation at break mechanical properties and the stability of wet of blend films had obvious effect. After the content of titanate coupling agent increased, the mechanical properties decreased and dissolve-loss rates increased gradually.