Nanocomposites of Poly(butylene succinate) (PBS) and poly(e-caprolactone) (PCL)-coated nano-TiO2 (C-TiO2) are prepared by melt-blending technique. The influence of high loading C-TiO2 on the microstructure, mechanical, thermal and dynamic rheological properties of pure PBS and its nano-composites are studied. Scanning Electron Microscope results demonstrate that the surface modification and content of TiO2 are main factors to affect the microstructure of composites. Mechanical tests show that adding C-TiO2 into PBS matrix is an effective way to improve the impact strength of the PBS. Impact property and tensile property are sensitive to different microstructure, the former is distance between particles and the latter is the aggregation of particles. Dynamic rheological tests show that the incorporation of C-TiO2 particles into PBS can improve the elastic properties of PBS nanocomposites and restrict the mobility of PBS chains. Differential scanning calorimeter indicates the addition of C-TiO2 can increase the crystallization rate but do not influence the main PBS crystals. Depending on the state of composites, the C-TiO2 restricts or improves the mobility of PBS molecules.