Cardiogenic unilateral pulmonary edema (UPE) is a rare clinical condition and not readily recognized early and managed accordingly. Acute rheumatic fever, which is a common disease in developing countries, does not commonly present with UPE. We report a 13-year-old girl presenting with UPE following acute rheumatic fever mimicking pneumonia. We conclude that UPE should be considered in the differential diagnosis for the patient with clinical criteria of rheumatic fever who presents with unilateral lung opacification. With early recognition and antifailure treatment, it is possible to reduce morbidity and mortality in such patients.