Background: Tunisia was one of the countries with the highest COVID-19 mortality worldwide. Although clinical characteristics and risk factors for severe disease in COVID-19 patients have been described in many studies, works on the pediatric population are still scarce. Objectives: The aim of our study was to describe the clinical characteristics of COVID-19 in pediatric patients in a tertiary care center since the start of the pandemic until the end of hospitalization to identify their association to severe forms. Methods: Since the start of the pandemic, the prevention and security of care department has been recording all new cases of COVID-19 hospitalized in the various units in which these patients were hospitalized. Daily monitoring of the evolution of the patient’s conditions was provided by the hygienist technicians of our department. Results: Overall, 180 confirmed COVID-19 pediatric patients have been admitted in our hospital. Most patients were male (51.1%); the median age was 1[1; 8] years. The median length of stay was 3 days [2-8]. Comorbidities were present among 43.9%: renal diseases (13.3%), coronary artery diseases (11.7%) and neurological diseases 6.7%. Most patients had an important degree of hypoxemia, with 12.8% of them requiring supplemental oxygen, and 4.4% needed intubation. The overall case fatality rate was 6.7%. The multivariate analysis revealed Independent risk factors which were: male gender (p :0.019, OR 1.363, IC [1.053-1.765]); use of nasal cannula ( p=10 -3 ; OR: 2.025, IC [1.397-2.933]); optiflow (p<10 -3, OR :11.042, IC [6.366-19.155]); noninvasive ventilation (p<10 -3,OR 24.14, IC [13.78-42.29]); comorbidities (p=0.001, 1.733[1.24; 2.42]) such as Hypertension, diabetes(p=0.016,1.44[1.07;1.93]), neurological disorders (p=0.025; 1.64[1.06; 2.53] and obesity (p<10-3;3.94[1.83;8.45]). Conclusions: identifying these risk factors is of tremendous importance to improve the management of pediatric patients at risk of severe forms and to guide the development of preventive measures.