Evidence is mounting that mitral valve repair can improve symptoms in adults with dilated cardiomyopathy. Data is currently lacking for children with dilated cardiomyopathy and options for annuloplasty are limited in children. We report on the successful management of a 21 month-old child in heart failure from dilated cardiomyopathy and severe mitral regurgitation. The echocardiogram showed severely dilated left heart cavities, severe mitral regurgitation from a dilated annulus (23 mm, Z-score 1.74) with discrete anterior leaflet tethering, and moderate systolic dysfunction. The mitral valve was repaired using a 16 mm Bioring Kalangos biodegradable annuloplasty ring. The patient was extubated on the third postoperative hour and discharged on the fifth postoperative day with trivial mitral regurgitation and a 5 mmHg mean transvalvular gradient. At 12 months, the patient is in NYHA class I and presents trivial central mitral regurgitation without any transmitral gradient. This represents the first report in successfully managing a child with dilated cardiomyopathy with mitral regurgitation using a novel biodegradable annuloplasty ring, which has the potential to durably remodel the mitral annulus and grow with the patient.