Different types of interstitial lung diseases (ILDs) develop in collagen vascular diseases (CVDs) such as scleroderma, rheumatoid arthritis, systemic lupus erythematosus, dermatopolymyositis, Sjogren's syndrome, and mixed connective tissue disease. These CVDs represent various histological patterns, including usual interstitial pneumonia, desquamative interstitial pneumonia, nonspecific interstitial pneumonia, bronchiolitis obliterance organizing pneumonia, diffuse alveolar damage, and bronchiolitis. The clinical presentations, prognosis, and response to treatment vary depending on the underlying CVDs, as well as histological patterns of ILDs. In general, the prognosis and survival rate of ILDs in CVDs are better than idiopathic ILDs. Optimal treatment also varies depending on the type of CVDs and the presence of interstitial lung disease, although in many cases, a combination of corticosteroids and cytotoxic drugs are given.