Summary. Background: The diagnosis of community-acquired pneumonia (CAP) is based mainly on the patient's medical history and physical examination. However, in severe cases a further evaluation including chest X-ray (CXR) may be necessary. At present, lung ultrasound (LUS) is not included in the diagnostic work-up of pneumonia. Aim: To describe the ultrasonographic appearance of CAP at presentation and during the follow-up. Methods: A total of 102 patients with clinical signs and symptoms suggesting pneumonia, who underwent a clinically driven CXR, were evaluated by LUS on the same day. LUS signs of pneumonia included subpleural lung consolidation, B-lines, pleural line abnormalities, and pleural effusion. The diagnostic gold standard was the ex-post diagnosis of pneumonia made by two independent experienced pediatricians on the basis of clinical presentation, CXR and clinical course following British Thoracic Guidelines recommendations. Results: A final diagnosis of pneumonia was confirmed in 89/102 patients. LUS was positive for the diagnosis of pneumonia in 88/89 patients, whereas CXR was positive in 81/89. Only one patient with normal LUS examination had an abnormal CXR, whereas 8 patients with normal CXR had an abnormal LUS. LUS was able to detect pleural effusion resulting from complicated pneumonia in 16 cases, whereas CXR detected pleural effusion in 3 cases. Conclusions: LUS is a simple and reliable imaging tool, not inferior to CXR in identifying pleuro-pulmonary alterations in children with suspected pneumonia. During the course of the disease, LUS allows a radiation-free follow-up of these abnormalities.