Background: Accurate diagnosis is essential for successful management of diffuse lung disease (DLD). Histopathology may sometimes be necessary. Surgical lung biopsy, the gold standard, carries a risk of morbidity and mortality. Computed tomography (CT) guided transthoracic lung biopsy (CT-TLB) is a minimally invasive method for obtaining lung tissue. However, its diagnostic yield is unknown in DLD. Objective: To assess the diagnostic yield of CT-TLB in DLD according to the predominant high-resolution CT (HRCT) patterns. Methods: Between January 2009 and December 2016, we enrolled all consecutive adult patients with suspicion of DLD who underwent CT-guided transthoracic lung biopsy during the diagnostic work-up. All biopsies were performed by a senior interventional radiologist using CT fluoroscopy. Results: The study included 169 patients (50.3% men) with a mean (±SD) age of 58.3 ± 14 years. Consolidation was the predominant HRCT pattern. A definitive or probable diagnosis was made in 66.3%. The most frequent diagnosis was organizing pneumonia (36.2%). Diagnostic yield was higher when the predominant HRCT pattern was consolidation or nodular. The most common complication was pneumothorax (17.8%); other complications included mild hemoptysis (7.7%), hemothorax (1.2%), and death (0.59%). No acute exacerbation of the underlying condition was observed. Conclusions: CT-TLB proved to be accurate and safe for the diagnosis of DLD. The overall diagnostic yield of the procedure was 66.3%. Given its low complication rates, CT-TLB can be an option in patients whose respiratory function is seriously impaired and in those with substantial comorbidities, where more invasive procedures cannot be performed for reasons of safety.