Objectives: This study aimed to assess the prevalence of oral mucosal lesions (OMLs) in patients attending outpa - tient dental clinics in Sana`a university, Yemen, and to evaluate the association of such lesions with age, gender, and oral habits. Materials and Methods: This cross-sectional study included 409 subjects (272 males, 137 females, age: 15-86 years). Detailed clinical examination was performed in accordance with international criteria. Patient history in - cluded age, gender, education, denture wearing and risk habits (tobacco use and qat chewing). Data were analyzed using SPSS 19.00. Results: The prevalence of OMLs was 58.4% with a significant difference between men (63.6%) and women (48.2%; P < 0.05). The most common lesions were fissured tongue (37.2%), hairy tongue (15.9%), tumors and tumor-like lesions (9.8%), qat-induced white lesions (9.3%) and racial pigmentation (5.9%). Overall OMLs pre - valence was linked to risk habits and age; qat chewing was statistically significant risk factor for having fissured tongue (OR: 1.77), hairy tongue (OR: 2.74), and white lesions (OR: 2.39) ( P < 0.05). Cigarette smoking was statis - tically significant risk factor for having hairy tongue (OR: 2.82), white lesions (OR: 3.60) and tumors and tumor- like lesions (OR: 2.91) ( P < 0.01). The increase in age was statistically significant risk factor for having tumors and tumor-like lesions (OR: 1.04; P < 0.001). Conclusions: The current results indicate that the occurrence of OMLs among Yemeni adults is high and emphasize that risk habits and age have some relationship with the presence of OMLs.