Coaxial electrospinning was developed for simultaneously electrospinning two different polymer solutions into core/shell nanofibers, or encapsulated bioactive molecular and drugs into polymer nanofibers for controlled release. In this study, heparin encapsulated poly(L-lactic acid-co-ε-caprolactone) [P(LLA-CL)] core/shell nanofibers were fabricated in water/2, 2, 2-Trifluoroethanol mixed solvent through coaxial electrospinning. TEM images clearly proved the core/shell structure of nanofibers when the proportion of feeding rates of inner and outer solutions was at 1:3. The morphology of these nanofibers were investigated and discussed from SEM micrographs, and the diameters showed a normal distribution. Furthermore, the fabrics of heparin encapsulated P(LLA-CL) core/shell nanofibers showed a strong inhibit ability on proliferation of fibroblast in cell viability test in vitro.