Covid-19 causedhospitalizations, severe disease and deaths in any age, including in the youngest children. The aim of this multicenter national study is to characterize the clinical and the prognostic role of lung ultrasound (LUS) in children with Covid-19. We enrolled children between 1 month and 18 years of age diagnosed with SARS-CoV2 infection and whounderwenta lung ultrasound within 6 hours from firstmedical evaluation. A total of 213 children were enrolled, 51.6%were male, median age was2 years and 5 months (IQR 4mm- 11 yearsand4 months).One hundred and fortyeight (69.4%) children were admitted in hospital, 9 (6.1%) in pediatric intensive care unit.We found an inverse correlation between the LUS score and the oxygen saturationatthe clinical evaluation (r = −0.16; p = 0.019). Moreover, LUS scores were significantly higher in patients requiring oxygen supplementation (8 (IQR 3 - 19) vs 2 (IQR 0 - 4); p= 0.001). Among LUS pathological findings, irregular pleural line, sub-pleural consolidations and pleural effusions were significantly more frequentin patients whoneeded oxygen supplementation (p = 0.007; p = 0.006 andp = 0.001, respectively). This multicentric study confirmed that LUS is able to detect Covid-19 low respiratory tract involvement, which is characterized by pleural line irregularities, vertical artifacts and subpleural consolidations. Notably, children with higher LUS score have an higher risk of hospitalization or need for oxygen supplementation, supporting LUS as a valid and safe point-of-care first level tool for the clinical evaluation of children with Covid-19.