Background: The aim of the study was to perform qualitative and quantitative computed tomography (CT) angiography-based evaluation of patent ductus arteriosus (PDA) morphology and its influence on morphology of the great vessels. Materials and methods: Two-thousand twenty-two patients underwent 64-slice or dual-source CT and were retrospectively screened for the presence of PDA. Those who had presence of PDA underwent evaluation of its anatomy and morphology. Results: Thirty-two adult patients with PDA were evaluated (mean age 41.4 ± 17.4 years). Subjects with PDA had a higher value of aortic isthmus (p = 0.0148), main pulmonary artery (p < 0.0001), right (p =0.0007) and left (p = 0.0074) pulmonary arteries diameters than individuals from control group (16 adults, median age 43.3 ± 12.4 years). Types A, B, C, D, and E of PDA morphology occurred in 16 (50%), 3 (9%), 9 (28%), 2 (6%), and 2 (6%) patients, respectively. Subjects with the type A configuration of PDA tended to have a larger diameter at the aortic orifice (10.2 ± 5.2 mm vs. 6.4 ± 4.9 mm, p = 0.09) and a larger maximal diameter (10.3 ± 5.3 mm vs. 7.1 ± 4.7 mm, p = 0.14) compared to subjects with the type C configuration. The values of minimal, mean, and maximal diameters of PDA were 4.7 ± 1.9 mm, 7.0 ± 3.2 mm, and 9.4 ± 5.0 mm, respectively. The Spearman correlation coefficient between the main pulmonary artery and PDA diameters demonstrated a good correlation for minimal (r = 0.70, p < 0.001), mean (r = 0.62, p = 001), and maximal (r = 0.60, p = 0.0003) PDA diameters. Conclusions: Computed tomography enables quantitative and qualitative evaluation of PDA, including its type of morphology, length, and diameters. In the evaluated adult population with PDA, the majority of patients had dilation of the aortic isthmus and pulmonary arteries. PDA diameters correlate with diameters of the pulmonary arteries and this correlation is strongest between PDA diameter at the narrowest site and main pulmonary artery. (Folia Morphol 2020; 79, 3: 462–468)