Objective: To investigate the characteristics of thin-slice CT images of the elderly and young patients infected with novel coronavirus pneumonia.Methods: 50 cases of old and young patients with positive novel coronavirus nucleic acid by laboratory fluorescence RT-PCR were selected, and the thin-slice CT findings of the two groups were analyzed retrospectively.Results: For the selected patients, the CT features of thin layer were mainly glass-like density, mesh, fibrosis and/or pulmonary consolidation. Among them,3 cases of single lung pure ground glass lesion in elderly group, bilateral lung ground glass lesion 47 cases:(1) bilateral lung pure ground glass lesion 21 cases; (2) 12 cases of bilateral lung glass consolidation; (3) 7 cases of pulmonary glass consolidation fibrosis; (4) 5 cases of interstitial lesions of bilateral lung grinding glass, diffuse distribution; (5) white lung in 2 cases, 2 cases of pleural effusion with extra-pulmonary changes. In the young and middle-aged group, there were 5 cases of single lung pure ground glass lesion, bilateral lung ground glass lesion 45 cases:(1) bilateral lung pure ground glass lesion 30 cases; (2) 9 cases of bilateral lung glass consolidation; (3) 6 cases of vitreous consolidation fibrosis. Besides, during CT imaging staging, 24 early lesions in aged group, 24 advanced lesions, 2 critical stage lesions. Early lesions in young and middle-aged group were 35 cases, 15 advanced lesions. There were 0 cases of critical disease. The above data indicated the composition ratio of advanced and severe stage in the elderly group was higher than that in the young and middle-aged group (P<0.05).Conclusion: By comparing the CT images of the elderly and the young and middle-aged patients, it is intended to improve the attention of the elderly patients and provide important imaging basis for clinical practice.