There are many articles related to child injuries during the coronavirus disease of 2019 (COVID-19) in other countries, but only few studies in this field in China. This study analyzes the clinical characteristics of unintentional childhood injury during the pandemic, to provide reference for the prevention of unintentional childhood injury in the context of pandemic. A comparative study was performed on the medical data of 2,497 children with unintentional injury who were hospitalized at Chengdu Women's and Children's Central Hospital between 1 January, 2018 and 31 May, 2021. The study period was divided into 2 periods, before the pandemic (1 January, 2018 to 31 May, 2019), during the pandemic (1 January, 2020 to 31 May, 2021). The number of unintentional childhood injuries and age distribution before and during the pandemic were compared. Group differences were examined using Mann-Whitney U for continuous variables and Chi-squared or Kruskal-Wallis tests for categorical variables. There were significant differences in age, accident location, hospitalization days, and medical expenses before and during the pandemic (P<0.05). During the pandemic, the number of children's unintentional injuries increased by 34.24% (1,066 vs. 1,431, P=0.000), and the significantly increased types of unintentional injuries included foreign bodies, falls, crush injuries, and sharp injuries. During the pandemic, the highest proportion of unintentional injury to children was foreign bodies, whereas the proportion of falls was the highest before the pandemic. During the pandemic, the number of foreign body injuries in toddler was significantly higher than before the pandemic (P=0.001), but the number of falls, crush injuries, and sharp injuries in preschooler was significantly higher (P<0.05). In the circumstance of the COVID-19, the number of foreign bodies, falls, crush injuries, and sharp injuries, in children increased significantly. It is necessary to strengthen the prevention of foreign bodies in toddler, and falls, crush injuries, and sharp injuries in preschooler.