A 14-year-old male was found to have a mediastinal mass on chest radiograph. Chest computed tomography scans showed a cystic lesion behind the left main bronchus. Magnetic resonance imaging revealed additional cystic lesions in the left chest and root of the neck. He underwent excision of mediastinal mass and a pleural cyst. The neck lesion was presumed to be a cystic hygroma. Histological examination of the two lesions resected showed them to be a foregut cyst and a benign mesothelial cyst. We know of no other report of concurrent multicystic lesions in the chest and neck and hypothesize that these cysts may have a common embryonic origin.