Connective tissue diseases (CTDs) are a heterogeneous group of idiopathic inflammatory diseases involving various organs. A thoracic involvement is frequent, and chest-CT represents the imaging technique of reference in its assessment. Pulmonary abnormalities related to CTDs are various; although several disease-specific aspects have been described, the two most clinically relevant complications are represented by interstitial lung disease and pulmonary arterial hypertension. The early identification of a thoracic involvement, with the adoption of specific therapies, can significantly change patient's prognosis. The aim of this article is to review the most common typical and atypical CT features of thoracic involvement occurring in CT, especially focusing on interstitial lung disease.