In our article we present the anatomical work of the distinguished Renaissance anatomist Realdo Colombo, as well as, his contribution to the discovery of pulmonary circulation. Colombo was not the first to describe the pulmonary circulation, but he backed up this hypothesis with evidence after extensive dissection and vivisection. He paved the way for his successors and particularly William Harvey (1578-1657) to the establishment of anatomy and physiology of blood circulation