Abstract: OBJECTIVE To explore the characteristics of CT images in patients with lobar pulmonary infection and pneumonia. METHODS 69 patients with lobar pulmonary infection and 54 patients with pneumonia-type lung cancer treated in the hospital from Jun.2013 to Jun.2017 were enrolled in the study.Patients with lobar pulmonary infection were taken as the experimental group and pneumonia-type lung cancer patients were taken as the control group.The types and composition ratios of pathogenic bacteria in lobar pulmonary infection were detected.CT scans were performed in both groups.The number of lesions and the distribution of single lesions were compared between the two groups.The imaging features of the two groups (bronchial congestion, nodule shadow, tumor display, and ground-glass surround) were examined and compared. RESULTS In 69 patients, 75 strains of pathogens were isolated, of which 24 strains of gram-positive bacteria accounted for 32.0%, 49 strains of gram-negative bacteria accounted for 65.3%, and 2 strains of other strains accounted for 2.7%.In the experimental group, 59 cases of single lesions accounted for 85.5%, and 10 cases of multiple lesions accounted for 14.5%.In the control group, 45 cases of single lesions accounted for 83.3% and 9 cases of multiple lesions accounted for 16.7%.There was no significant difference in the number of lesions between the two groups.There were significant differences in CT findings between the two groups in terms of bronchial congestion, nodule hyperplasia, tumor display, grinding glass shadow, and cystic transillumination (P＜0.05). CONCLUSION There was no difference in the number and distribution of lobar pulmonary infections and pneumonia-type lung cancer lesions.CT images showed differences in bronchial congestion, nodule shadows, tumor display, ground glass shadow and cystic transillumination.Attention should be paid to the identification of the above CT image features during the examination.