Abstract: Objective The present investigation was intended to explore the clinical characteristics and epidemic process of mild acute respiraory infection in the city of Dongtai in order to provide a scientific basis br the prevention of spread of the disease Methods 174 cases of hospitalized patients with mild acute respiratory infection in the towns of Xuhe and Sancang were selected and epidemiological investiga-tion was carried out in terms of basic condition，clinical manifestation，therapeutic turnover and contact history of patients，followed by summary analysis Results(1)The epidermic occurred mainly in May and June with cases principally distributed among primary and middle schools and kindergartens in towns and districts. (2)Clinical characteristics included fever，pharyngalgia，swelling of tonsil，increased lung marking and increase in leucocytes and neutrophils.(3)Pharyngeal swabs and blood samples were obtained from patients for etiological tests，conducted by Jiangsu CDC，Fndan University and China CDC，and it was showed that adenovirus (Type Ⅲ)infection was the main cause of this disease Drags such as Azithromycin，Cefuroxime and virazole showed better therapeutic efficacy.(4)Most patients had a con- tact history of other patients with a similar disease before onset，with an average latent period of 4-5 days. Conclusion Mild acute respiratory infection is highly infective and has a quick transmission，but the virulence of pathogens is relatively weak and hence symptoms are not serious The reinforcement of epidemic monitoring，early detection of patients，reduction of contact between dassmates，promotion of food，drinking water and environmental hygiene，as wdl as enhancement of individual sanitation and prevention are major interventions to control transmission of the disease.