Objective To summarize the clinical characteristics of influenza A and influenza B in children. Methods Five hundred and ninetynine cases treated in Beijing New Century Women and Children’s Hospital between April 2015 and March 2016 were divided into influenza A group and influenza B group. All the data was inputted and statistically analyzed using JMP software. Results Patients with influenza A and influenza B did not show significant difference in gender. Influenza A was prevalent among children under 4 years old, but the median age of patients with influenza A, which was 3.5 years, was younger than that of influenza B, which was 4.5 years. Influenza was more prevalent in winter than in spring. Cases of influenza A accounted for 45.8% of the total and those of influenza B made up 54.2% in a year. The incidence of influenza A was 53.9% and that of influenza B was 46.1% in winter. The incidence of diarrhea among children under 4 years of age was much higher than among those above 4 （P=0.0251）. Conclusions Influenza often occurs in infants and young children under 4 years old. Winter and spring are seasons in which influenza A and B often occur.Cases of influenza B tend to increase in spring. The proportion of diarrhea symptoms in children with influenza less than 4 years old is significantly higher, suggesting that children who have diarrhea are at risk of influenza in the flu season.