Abstract: Objective To analyze the clinical characteristics of adenoviral pneumonia (AP) in children, so as to improve the clinical diagnosis level of AP, diagnose AP as early as possible, reduce the incidence of short-term and long-term adverse prognosis, improve the quality of life and survival rate, and reduce the case fatality rate. Methods The clinical data of 120 hospitalized AP children in our hospital from June 2017 to June 2019 were retrospectively analyzed. AP children were divided into mild AP (90 cases) and severe/critical AP (30 cases) according to the "guidelines for the diagnosis and treatment of children with community-acquired pneumonia (2019 Edition)". Gender, age, heat course, pulmonary signs, pulmonary imaging, WBC, Hb, CK-MB, liver function and other indicators were analyzed and compared between the two groups. Results Among the 120 AP patients, 24 (20.00%) were ≥ 24 months, 96 (80.00%) were<24 months, and 90 (75.00%) were from 6 months to 24 months. The ratio of male to female was 2.53:1, and 95 cases (79.20%) were found in winter and spring. All the cases were febrile, with 84 (70.00%) cases of high fever and 62 (51.67%) cases of heat path ≥ 7 days. There were 106 cases of cough (88.33%) and 45 cases of wheezing (37.50%). Pulmonary imaging showed that the number of involved lobes ≥ 2 (macrophylla) in 16 cases (13.33%). There were 11 cases (9.20%) of lung consolidation and 7 cases (5.83%) of pleural effusion. In the comparison between the mild AP and severe/critical groups, statistical analysis was conducted for younger age, high fever ≥ 7 days, multiple organ damage, number of involved lobes ≥ 2, basic disease, and more than one pathogen (all P<0.05). The most common complications were myocardial and liver damage. Conclusion Clinically, young, in prone season, with persistent high fever>3 days, with basic diseases, more than one pathogen infection, inflammation index increased significantly, X-ray suggests involvement>2 leaves or pleural effusion, should be checked early line of adenovirus pathogens, diagnosis, treatment as soon as possible, reduce the critically ill, improve child survival quality and survival rate, reduce the case fatality rate.