Summary Introduction Primary frontal sinus cancer is rare tumor of the paranasal sinuses. Tumors in the frontal sinuses are more often extensions from the ethmoid sinus – secondary involvement. The authors present a case of man with primary squamous cell carcinoma of the right frontal sinus. Material and methods A 49 years old man was admitted to the Dep. of Otolaryngology with right frontal sinus tumor. The man had painless forehead and upper lid swelling followed by orbital symptoms – diplopia. CT showed large destruction of anterior frontal sinus wall and invading thought inferior wall to the orbit. The patient was qualified to frontal sinus operation with right orbit content removal. Histopathologic postoperative examination showed squamous cell carcinoma G2 of right frontal sinus. Results A combined treatment, surgery and postoperative radiotherapy succeeded in good result. The 5-year survival rate in this case is 100%. Conclusions Frontal sinus cancers are rare and diagnosed in late clinical stage. The treatment is both, surgery and obligatory postoperative irradiation. The effect of treatment is still insufficient in most cases.