Objectives: To analyze the frequency and type of the most common benign tumors of the oral mucosa found at the Hospital Stomatology Service, and to study the clinical characteristics and possible etiological factors. Material and Methods: This is a retrospective study of 300 patients with histologically diagnosed benign tumors of the oral mucosa. Data was compiled for each case, documenting information relating to age, gender, medication, habits (smoking, oral hygiene), anamnesis (reason for consultation, symptomatology, evolution), and the characteristics of the lesion (site, color, size, surface, consistency, and base). Results: Of all the tumors studied, 53% were histologically diagnosed as fibroma. In the study of prevalence of benign tumors of the oral mucosa, no differences were found for age; however there were differences according to gender, finding a greater prevalence of fibromas, pyogenic granulomas, and giant cell granulomas in women, at a ratio of 2:1. The group of tumors studied showed a significantly asymptomatic behaviour, and self-limiting and slow growth. With respect to the possible etiologic agents, we found no statistically significant differences between them. Conclusions: Following the study of 300 patients histologically diagnosed with benign tumor of the oral mucosa, we can state that with regard to prevalence, we found significant differences with respect to gender, being more frequent in women. The fibroma is the most frequent benign tumor of the oral cavity.