INTRODUCTION Malignant tumors of the paranasal sinuses are traditionally managed through external approaches. Advances in endoscopic transnasal surgery have allowed for the endoscopic treatment of some of these tumors. AIM To present the results of treatment of a series of patients with paranasal sinus malignancies treated with an endoscopic approach at a single institution. MATERIAL AND METHODS The data on tumor type, operative technique, perioperative complications and postoperative course were analyzed. RESULTS Eleven patients meeting the inclusion criteria were identified. The histopathology was as follows: malignant melanoma in 3 patients, squamous cell carcinoma in 2, adenocarcinoma in 2, poorly differentiated carcinoma in 1, hemangiopericytoma in 1, adenoid cystic carcinoma in 1 and fibrosarcoma in 1. There were no severe perioperative complications with the exception of 1 case of cerebrospinal fluid leak, which was successfully closed. The mean observation period was 13.5 months. One of the patients died of disease, another was lost to follow-up, and one was reoperated on due to recurrence. The remaining 8 patients are alive with no signs of recurrence. CONCLUSIONS Our initial experience seems to confirm results obtained by other authors indicating that in selected cases endoscopic surgery of sinonasal malignancies is similarly effective as external approach surgery.