Lung disease in patients with juvenile arthritis with systemic onset (sJIA) is a rare, poorly understood and prognostically unfavorable complication. Lung diseases are represented by interstitial lung disease, pulmonary alveolar proteinosis/lipoid pneumonia, pulmonary arterial hypertension. The main predictors of lung diseases are the early onset of sJIA, the predominance of systemic manifestations over articular, macrophage activation syndrome, therapy with genetically engineered biological drugs, and an anaphylactic reaction to tocilizumab. The article presents three clinical observations of lung diseases in patients with SJIA and analysis of literature data.