Objectives: Granulomatosis with polyangiitis (GPA) affects respiratory system very often. In this report, we document the pulmonary manifestations and computed tomography (CT) findings in GPA patients. Subjects and Methods: We conducted retrospective study of GPA patients followed up at King Khalid University hospital, King Saud University, Riyadh, during the period 1990–2014. Various disease manifestations, X-ray and CT findings, therapy, and outcome in GPA patients with pulmonary involvement were retrieved. Results: Among 23 cases of GPA, 14 were males and 9 were females. Mean age at onset of disease was 42.1 ± 14.5 (range: 11–63) years. Respiratory tract was the most frequently involved system (82.6%); upper airways were affected in 56.5% and lungs in 65.2% patients. Among 19 patients with respiratory system involvement antineutrophil cytoplasmic antibody (ANCA) was positive in 18 (94.7%) patients; c-ANCA was positive in 15 (78.9%) and p-ANCA was positive in 3 (15.8%) patients. Chest CT findings in 15 patients showed that lung nodules were the most frequent pathologies, seen in 12 (80.0%) patients, and were cavitated in 8 (53.3%) patients. Airspace opacification was seen in 73.3%, air bronchogram in 20.0%, and ground-glass opacities in 33.3%. CT results at follow-up showed resolution of lung nodules in 9 (60.0%) patients. Lung biopsies showed chronic granulomatous inflammation with vasculitis and necrosis. Intravenous cyclophosphamide was received by 63.2% patients and 10.5% required rituximab therapy along with other drugs. Conclusion: Respiratory system involvement in our GPA patients was similar to previous reports but with variation in certain parameters. Disease outcome was good, and lung CT at follow-up showed resolution of nodules with treatment.