Introduction. The aim of this paper was to report a case series of three patients diagnosed with multiple primary synchronous cancers (MPSC) in the lungs who were treated multidisciplinary at a single-center institution. Outline of cases. Three male patients were referred to the Clinic for Chest Surgery, at the Military Medical Academy in Belgrade, Serbia for planned surgical treatment of lung cancers. During subsequent diagnostic procedures, second primary synchronous tumors were detected in all presented cases. All patients underwent surgical resection and chemotherapy or a combination of chemo- and radio-therapy. Two out of three patients died with an average survival period of 32 months. One patient is still alive, with current disease-free interval of 21 months. Conclusion. MPSC is a rare condition. The final diagnosis should be based on clinical, radiological, histopathological, and genetic analyses. Treatment modalities of MPSC depend on the clinical staging of the disease, patient?s general medical condition, and general assessment of tumor operability and resectability.