Pulmonary veins stenosis in a Down Syndrome infant with normal connection pulmonary vein is rare and precise incidence of this disease is unknown. We report a case of progressive multiple pulmonary vein stenosis in a Down Syndrome infant with congenital heart disease and transient myeloproliferative leukaemia. This case-report aims to improve awareness among physicians and sonographers of this disease and the importance of pulmonary vein assessment in congenital heart disease with unexplained pulmonary hypertension.