We describe a male infant with biopsy-confirmed interstitial lung disease (ILD) who responded to chloroquine, after he failed to improve on oral corticosteroids or cyclophosphamide. The infant presented at 8 days of age with respiratory distress and cyanosis. Lung biopsy at 8 weeks of age was consistent with desquamative interstitial pneumonitis (DIP). He was treated with corticosteroids at 2 weeks of age because of a family history of two siblings who died during infancy and who had DIP on postmortem examination. At 8.5 months, our patient was treated with cyclophosphamide because of lack of response to corticosteroids therapy. At 14 months of age, he began treatment with chloroquine in addition to corticosteroids and had a dramatic response within 3 weeks. The patient has been maintained successfully on continuous treatment with chloroquine alone for more than 9 years since this treatment was started.