Systemic lupus erythematosus in infants born to healthy mothers is a rare entity. We describe a male infant who presented at 1 month of age with pulmonary hemorrhage and glomerulonephritis due to systemic lupus erythematosus, confirmed serologically and histologically. He was managed with a combination of prednisone and intermittent cyclophosphamide, but also received mycophenolate mofetil, with a complete serological and clinical remission at 30-month follow-up. This case underscores the importance of a broad approach to the evaluation of pulmonary hemorrhage and glomerulonephritis in the very young and the need for aggressive immunosuppressive therapy to achieve sustained serological and clinical remission.