Acute pericarditis in children is a common condition, defined by inflammation of both pericardial sheets, with or without associated pericardial effusion. We conducted a retrospective descriptive study of 50 cases of acute pericarditis in children, collected in the pediatric cardiology department at La Rabta Hospital over a period of 30 years. The mean age was 7.5±1.5 years, with a gender ratio of 1.78.Chest pain, the major symptom, was present in 30% of cases; accompanying signs were dyspnea in 76% of cases, fever in 68% of cases.the electrocardiogram showed electrical abnormalities in 60% of cases.radiologically, cardiomegaly was present in 82% of cases, and pleural effusion in 12% of cases. All children showed pericardial effusion on ultrasound, which was circumferential in 74% of cases.60% of cases showed a biological inflammatory syndrome.Management was symptomatic, combined with etiological treatment, with a favorable outcome in 72% of cases.Only one death was noted, and 4 cases of relapse.