Abstract: objective: To analyze CT features of pulmonary tuberculosis complicated by low immunefunction patients. Methods:38 cases of confirmed CT images of pulmonary tuberculosis in immunocompromised patients were collected, anglicizing from the lesion types, distribution, size, configurations of focus, property and lymphatic pathological changes, etc. Results : the most of CT images of pulmonary tuberculosis in immunocompromised patients caught infiltrative pulmonary tuberculosis, the lesions distributed widely, the consolidation(38/38, 100%), nodules(21/38, 55%), cavitations(16/38, 42.1%), lymphatic pathological changes(11/38, 28.9%) were typical manifestation, which accompanied emphysema, hardening and calcified fibrous bands, the stenosis and dilatation of bronchus and pleural changes, etc. Conclusion: the CT images of pulmonary tuberculosis complicated by low immune function patients are complex and changeable, the features of which include that the pathogenic location and CT symptom are both atypical, the extent of disease is wide, the multi-character focus coexist and spread easily, the lung is damaged seriously and the prognosis is poor. CT diagnosis with medical history and clinical material attach positive significance to clear diagnosis.