Oral cancer, the most common cancer of the head and neck region, ranks eighth among the most prevalent cancers in the world. Despite advances in technology and treatment the survival rate has not been improved in the last decades. Oral cancer affects not only the quantity but also the quality of life (QOL). The present study investigated for the first time the burden of oral cancer in Tehran, Iran in terms of patient and tumor characteristics, survival rate, and delay in diagnosis. At the time of diagnosis, most oral cancer patients were at advanced stages. Oral cancer patients’ survival was negatively associated with tumor stage at diagnosis. The findings of this study revealed that the total time elapsed between the onset of symptoms and diagnosis, the diagnostic delay, was high. This may explain the low survival rate of the oral cancer patients. Based on the findings, developing preventive programs that focus on raising public awareness about the signs and symptoms of oral cancer is essential in promoting earlier diagnosis of oral cancer in Tehran, Iran. This study should be especially useful to professionals in oral health fields.