Isolated unilateral absence of pulmonary artery is quite rare and usually associated with congenital cardiac defects. It is usually diagnosed in childhood with recurrent respiratory tract infections and signs of pulmonary hypertension. It rarely remains asymptomatic until adulthood and may present with dyspnea, hemoptysis, and recurrent respiratory infections later, while it can rarely be an incidental finding of other imaging. Surgical management in early days of life will prevent pulmonary hypertension while in adults it is aimed to treat the complications. Here, we report the case of a 77-year-old female, a mother of five children. She came with worsening of dyspnea for a week, and her computed tomography pulmonary angiography showed absence of left pulmonary artery accompanying hypoplastic lung. Ventilation perfusion imaging showed absence of perfusion of the left lung. She had severe pulmonary hypertension and was managed with long-term oxygen therapy, diuretics, and vasodilators.