Nocardia is Gram-positive, weakly acid-fast, catalase-positive, nonmotile, branching rod-shaped aerobic bacteria, belonging to actinomycetales. 1,2 Nocardia widely exists in soil, water, air, and rotten plants. It is common in patients with T-cell deficiency (leukemia or AIDS), long-term usage of immunosuppressants (such as organ transplantation and malignant tumor), or patients with underlying diseases (such as diabetes and chronic kidney disease). [3][4][5][6] Pulmonary nocardiosis is a purulent and granulomatous disease caused by Nocardia invading the lung through respiratory tract inhalation or skin lesions. It can spread into the brain, kidney, and other organs by blood dissemination and even form life-threatening sepsis.The clinical manifestations of pulmonary nocardiosis are fever, cough, expectoration, dyspnea, chest pain, hemoptysis, weight loss, fatigue, and other symptoms. Pulmonary nocardiosis is commonly characterized by infiltrative lesions, cavities, nodules, or masses in lung segments or lobes in computed tomography. Because its clinical manifestations and imaging are not specific to common bacterial infection, pulmonary aspergillosis, lung cancer, pulmonary abscess,