Background: Mesenchymal Stromal Cells (MSC) possess diverse immunomodulatory and regenerative properties, and play an essential role in tissue homeostasis, surveillance and repair, mainly mediated via paracrine signaling. MSC have been largely studied regarding therapeutic potential for a variety of immunological and degenerative diseases. Clinical applications of MSC-based therapy require scalable expansion process and Good Manufacturing Practice (GMP) compliant production. Inconsistency of the therapeutic potential and low survival of transplanted cells require search for priming/preconditioning strategies and new approaches GMP-compliant expansion to produce robust and functional MSC products. Aim: Establishment of a GMP and scalable bioprocess for hypoxia-primed UC-MSC expansion and analysis of in vitro paracrine potential of primed cells. Methods: MSC from umbilical cord (UC-MSC) were expanded for 5 days under xenoantigen-free conditions primed with hypoxia (oxygen concentration of 5%) in a three-dimensional culture using microcarriers and stirred-tank bioreactor system. Harvested cells were characterized by immunophenotyping and differentiation potential. The paracrine angiogenic potential of expanded/primed UC-MSC upon human umbilical vein endothelial cells (HUVEC) was evaluated by the capillary-like structure assay performed in Matrigel-Growth Factor Reduced Membrane and scratch/gap closure assay, using conditioned medium (CM) from stirred cultures. Results: UC-MSC exhibited efficient and similar expansion in stirred system under both conditions 1.69 (±0.29) ×105 cells/mL in hypoxic and 1.74 (±0.23) ×105 cells/mL in normoxic culture, a fold increase of 6.98 (±1.08) and 7.46 (±2.0), respectively. Cells retained their immunophenotype and differentiation ability. CM from hypoxia primed-MSC promoted higher HUVEC migration rates compared to normoxic cultures 64.9% (±0.04) vs. 45.7% (±0.08), and higher formation of capillary-like structures in Matrigel. Conclusions: These results represent an important step toward the establishment of a GMP-compliant large-scale production system for functional hypoxia primed UC-MSC, and confirm higher angiogenic capacity of these cells in vitro. New experiments are needed to evaluate the effect of priming with hypoxia to immunomodulatory and angiogenic in vivo potential.