Dynamic mechanical properties, structure and morphology of tetraethoxysilane/poly(epsilon-caprolactone) (TEOS/PCL) hybrid materials have been analysed by dynamic mechanical spectroscopy, small-angle X-ray scattering, transmission electron microscopy, and image analysis. The experimental observations agree with a microscopic phase separation of the two constitutive components : the organic polymer and the silica network. The effect of the PCL functional end-groups, the number of functional end-groups per PCL chain, the PCL molecular weight and content, and the curing conditions have been studied on the structure and properties of the hybrid materials. Finally, phase morphology has proved to be co-continuous, at least when the weight composition is close to 50% for each component (SiO2 and PCL), with a characteristic length between the PCL and silica phases of ca. 5 nm, as estimated by image analysis of transmission electron micrographs.