Abstract: Polycaprolactone-grafted-starch (PCL-g-St) was synthesized with caprolactone and corn starch using tetrabutyl titanate as initiator via coordination-insertion ring-opening polymerization. PCL-g-St and corn starch were compared using FTIR and DSC. The blend of PCL and PCL-g-St was prepared, and the mechanical properties, hydrophobicity, interface properties of the blend were investigated. The results show that the compatibility of the two phases in the blend is effectively improved after the starch was grafted with PCL and the mechanical properties are also increased compared with a non-modified St/PCL blend. The hydrophobicity of the PCL-g-St/PCL blend is improved, and its mechanical properties are not much influenced after being soaked into the water.