【Abstract】Objective To analyze the distribution characteristics of respiratory viruses and special pathogens in children with congenital heart disease complicated with community-acquired pneumonia and children with simple community-acquired pneumonia. Methods 721 children with community-acquired pneumonia hospitalized in our hospital from January 2014 to August 2019 were retrospectively analyzed. According to whether the children had congenital heart disease, they were divided into congenital heart disease group (CHD group) with 208 cases and simple community-acquired pneumonia group (LRI group) with 513 cases. Indirect immunofluorescence method was used to detect the serum levels of Legionella pneumophila IgM antibody (LP1A), Mycoplasma pneumoniae IgM antibody (MPA), Rickettsia Q fever IgM antibody (QR-FA), Chlamydia pneumoniae IgM antibody (CPNA), adenovirus IgM antibody (ADVA), respiratory syncytial virus IgM antibody (RSVA), influenza A virus IgM antibody (IAVA), influenza B virus IgM antibody (IBVA) and parainfluenza. There were 9 kinds of respiratory tract pathogen antibodies and specific pathogen IgM antibodies. The positive rate of 9 kinds of respiratory pathogens and special pathogens, the distribution of different ages and seasons were compared between the two groups. Results The total positive rate of IgM in CHD group (65.4%) was higher than that in LRI group (59.4%), but there was no significant difference between the two groups (P＞0.05). In CHD group and LRI group, Mycoplasma pneumoniae (MP) was the most common, followed by influenza B virus (IBV), and the positive rate of other viruses and respiratory special pathogens was low. Compared with LRI group, CHD group was more likely to be infected with MP in infancy, but it was more likely to be infected with IBV in 1-3 years old (all P＜0.05). In winter and spring, CHD group was more likely to be infected with MP and IBV, while LRI group was more likely to be infected with Lp1 and adv, but the positive rate of Lp1 in both groups was low, which had no clinical significance. Conclusion The specific pathogen antibody spectrum of children with CHD complicated with community-acquired pneumonia was similar to that of children with simple community-acquired pneumonia, and MP was the most common. In infancy, winter and spring, children with CHD combined with community-acquired pneumonia are more likely to be infected with MP than children with community-acquired pneumonia alone. It is easy to be infected with IBV in 1-3 years old and winter and spring.