Objective:To analyze the early clinical features of children with coronavirus disease 2019 (COVID-19) in order to further improve the understanding of the disease.Methods:A total of 312 children with COVID-19 under 16 years old who were first diagnosed in the children′s fever clinic at Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine from March to May 2022 were retrospectively analyzed.The epidemiology, early clinical features and blood routine results of children were described, and the blood routine results among different age groups were compared.Results:The median age of 312 children was 3.15(1.47, 6.51) years.The proportion of infection rate of children with different ages from high to low were 1~3 years old, > 6 years old, 3~6 years old and ≤ 1 year old.Only 17 (5.4%) cases had underlying diseases.Additionally, 70.2% patients had definite positive case reports in their residential communities, and 65.1% showed a familial cluster.Moreover, 96.2% patients had fever and 52.9% patients had respiratory symptoms.The main symptoms are fever (96.2%), cough (38.1%), runny nose (20.2%), vomiting (14.7%), sore throat (11.5%), poor appetite (6.7%), nasal congestion (4.5%), expectoration (4.5%), convulsion (4.2%), diarrhea (3.8%), etc.Among 309 children, 11.3% patients had increased white blood cell count, especially in children over 6 years old ( P=0.006); 31.7% patients had decreased lymphocyte count and 32.4% had increased C-reactive protein.The positive rate of point-of-care testing was as high as 99%. Conclusion:Children with COVID-19 in Shanghai had the characteristics of familial cluster.The main symptoms are fever and respiratory symptoms.Most of the blood routine leukocytes have no obvious changes, and a few have lymphopenia and C-reactive protein elevation.Point-of-care testing detection can help the children′s fever clinic to early screen COVID-19.