Mycoplasma pneumoniae is a common cause of community-acquired pneumonia in children, while lung abscess is a severe complication of bacterial pneumonias caused mainly by pyogenes. Here we report a previously healthy 10-year-old boy admitted to our unit for a right upper lobe pneumonia, with a 15-day history of fever and cough insensitive to oral amoxicillin and intramuscular ceftriaxone. Chest computed tomography scan revealed that the right upper lobe consolidation was an abscess and that a similar formation was present in the right mid region. Serology allowed the diagnosis of M. pneumoniae infection. The clinical picture rapidly improved after initiation of oral clarithromycin, and radiographic resolution, without sequelae, was observed after 1-month treatment. Lung abscess in children is a rare complication of M. pneumoniae infection and only three previous cases have been described in the literature, all associated with a delayed diagnosis and late initiation of macrolide therapy. A long-term treatment with oral macrolide allows a prompt recovery and restitution ad integrum of the lung.