The differential diagnosis of acute rheumatic fever (ARF) in children, especially those younger than five years, may be difficult, even with strict application of the updated Jones criteria. They are likely to present with atypical symptoms that can mimic various conditions. Herein we report a 27-month-old girl with ARF presenting unilateral pulmonary edema secondary to severe mitral regurgitation. Taking into account atypical clinical presentations in these younger ARF patients will prevent the delay in the diagnosis and will have an impact on treatment to reduce morbidity and mortality of the disease.