Oral cavity squamous cell carcinoma (OCSCC) is a malignant tumour of epithelial descent. The tumour appears most frequently with people who smoke cigarettes and drink alcoholic beverages. Oral cavity squamous cell carcinoma can appear anywhere in the oral cavity, but the most common sublocalizations are the floor of the mouth and the ventral surface of the tongue. The major metastatic path for squamous cell carcinoma is the one to the cervical nodes. We choose the type of surgical treatment depending on the existence of regional metastases and the size (T stage) and the sublocalization of primary tumour. The aim of our retrospective study was to determine the incidence, sublocalization, TNM classification and the method of treatment of the oral cavity carcinoma. The study included 1097 patients with squamous cell carcinoma of the oral cavity who were treated on the Department of Maxillofacial Surgery, University Hospital Dubrava during the period of 20 years. The results have shown that the OCSCC is more common in males than in females (5:1), with the most common sublocalization being the floor of the mouth. The carcinoma was most evident and therefore most commonly diagnosed in the T2 stage, and the surgical treatment that was generally used was the intraoral excision.