Abstract: Objective: To analyze the relationship between chest computed tomography (CT) findings and clinical typing of omicron variant strains of coronavirus disease 2019 (COVID-19) at different ages, so as to improve the understanding of the imaging manifestations of COVID-19. Methods: Chest CT data of 75 patients with COVID-19 were retrospectively analyzed, including 40 males and 35 females, with an average age of (46.2±17.2) years. They were divided into groups A, B, and C based on different age groups. The differences in chest CT lesion distribution, lobular involvement, number and density, and clinical classification among the three groups were compared. Results: All 75 patients infected with the omicron variant had an epidemiological history, and no statistically significant difference was noted in gender among all clinical types. The mean age of patients with severe and critical symptoms was higher than that of patients with mild and common symptoms, and the distribution in the upper lobe of the left lung, upper lobe of the right lung, and middle lobe of the right lung was higher than that of the common type. In patients with severe symptoms, the distribution of lesions in the left lower lobe and both lungs was higher than that in the common type. The lesions were mainly ground glass opacity and consolidation. The proportion of severe and critical type increased in groups A, B and C, and the lesion range was larger than that of the common type. Conclusion: All patients with COVID-19 who were infected with the omicron variant have an epidemiological history. The clinical classifications and chest CT signs of patients in different age groups have certain characteristics, and familiarity with these characteristics can help predict severe COVID-19.