This case report presents the prenatal diagnosis of type A persistent fifth aortic arch (PFAA) at 22 weeks gestation, identified by parallel vessels and bifurcated blood flow below the normal aortic arch. Postnatal evaluation confirmed PFAA with muscular VSD and limb abnormalities. Whole exome sequencing detected 14mb repeats at 9q33.3-q34.3, proving that PFAA was associated with chromosomal abnormalities. This case highlights the diagnostic value of ultrasound long-axis aortic arch view in detecting this rare abnormality.