Dead space formation in the thoracic cavity as a result of lung parenchymal resection is particularly prone to intra-thoracic infections, which are often hard to treat with systemic antibiotics: secondary interventions, such as thoracoplasty, eloesser flap, or muscle flap may be required to treat this complication. Alternatively, use of an omental flap represents an attractive option in cases of surgical cavities, due to the volumetric and immunologic advantages associated with the omentum. A 55-year-old male patient, who underwent left upper lobectomy due to an aspergilloma, was left with a surgical cavity that became infected with Pseudomonas aeruginosa. To address this complication, we performed a reconstruction of the left upper lung field through the substernal route using a section of the omental flap, and the infection was clinically eradicated.