ObjectiveTo realize  pathogens and infection characteristics of acute respiratory infections in children.Methods1 410 hospitalized children with acute respiratory  infection were selected from a hospital in 2011. Seven  types of viruses(parainfluenza virus Ⅰ, Ⅱand Ⅲ,Influenza virus A and B,respiratory syncytial virus  and adenovirus) were detected by direct immunofluorescence assay, bacteria were cultured.  Viral infection rate in different months, different ages, and associated infection were analyzed. ResultsOf 1 410 specimens, 594 (42.13%) were detected positive for virus, and the main viruses were respiratory syncytial virus and adenovirus; 258 (18.30%) specimens were detected positive for bacteria. Virus detection rates were high in March, April, October and November(all>50%), while low in JulySeptember (22.89%-31.40%);Virus detection rate  was high in 1-3 year age group(58.04%), while low in 6-14 year age group (22.15%). Mixed virus were detected  in 22  (1.56%) specimens, 157 children (27.45%) had coinfection of single virus and bacteria. The coinfection rate of influenza virus A or B and bacteria was 47.06% and 47.27% respectively.ConclusionRespiratory virus infection rate in children is associated with age and season. After viral infection, the associated bacterial infection is relatively higher, influenza virus A and B are more easily associated with bacterial infection.