Since 2019 coronavirus disease (COVID-19) is highly contagious with a high mortality rate. France has taken strict infection control measures. According to the report by the Center for Disease Control and Prevention, children are less affected with COVID-19 and seem to have less severe disease than adults. We reported the first confirmed infant case of co-infection with SARS-CoV-2 and Citrobacter koseri urinary infection in 6-week-old child admitted on 25 March 2020 with mild symptoms in the Pediatric COVID Unit of Amiens University Hospital, France.