Introduction: Synthetic vascular grafts are widely used in large diameter vessels. However, in vessels < 6 mm of diameter, they have a high failure rate due to thrombus formation. Electrospun scaffolds functionalized with biomolecules, such as heparin (Hep), can be an interesting tool for use as vascular grafts. The Hep can improve the vessel regeneration and prevents the failure of graft by thrombi formation. For blood vessel regeneration, the establishment of vascular endothelium is the initial goal for the success of the grafts. Endothelial progenitor cells (EPCs) demonstrate a high capacity of angiogenesis and vasculogenesis, contributing to graft endothelization. Aim: To evaluate the in vitro cultivation of EPCs on polycaprolactone (PCL) electrospun scaffolds functionalized with nanocapsules (NC) containing Hep. Methodology: PCL scaffolds were produced by the electrospinning technique. After their production, the scaffolds were functionalized with NC containing Hep. To achieve this, the NC were deposited on the scaffolds through the electrospraying technique, from a emulsion of poly(lactic-co-glycolic acid) (PLGA) and Hep. Following this, the EPCs were cultivated on the scaffolds. Three groups were evaluated: PCL with empty NC (PCL/NE), PCL with NC containing Hep (PCL/Nhep) and a culture plate treated with collagen (control group). The biological characterization of the scaffolds was made in terms of cell morphology, adhesion and viability. To evaluate EPC morphology, their nuclei were labeled with DAPI and the cytoskeleton with phalloidin. For cell adhesion, the cells were labeled with DAPI and observed under fluorescence microscopy. Nine random fields from each sample were analyzed, using the LAS × software, where it was possible to estimate the number of adhered cells/sample. For viability test, the cells were cultivated for 1, 3 and 7 days and analyzed by MTT. Results and discussion: In the cell adhesion test, the control group showed 1191±412.6 cells/sample, considered to be the group with the highest number of cells than the others. The scaffolds groups had similar cell adhesion: PCL/NE 697.5±309.7 and PCL/Hep 692.5±145.1 cells/sample. The cell viability showed results similar to those of adhesion. The control group showed superior viability to the scaffold groups (p<0.05) in the three periods evaluated while the PCL/NE and PCL/NHep showed similar absorbance. The control group was treated with collagen, an endogenous component of extracellular matrix, which favors the adhesion and growth of EPCs. However, although the control group obtained grater cell adhesion than the other groups, the scaffolds also prompted cell adhesion and provided a 3D structure that can be used in vascular tissue engineering. In addition, the MTT test demonstrated that the viability of EPCs increased during the cultivation time on the scaffolds groups. Moreover, after 7 days of cultivation, the EPCs showed elongated morphology on the scaffolds, indicating that the cells had good adaptation on these structures. Conclusion: The scaffolds favored EPC adhesion and growth during the evaluated time. In addition, the presence of NC did not alter these parameters. These resulted demonstrated that the developed scaffolds can be an interesting alternative for vascular tissue engineering.