Background and Objective: Oral cancer accounts for less than 3% of all cancers. Despite recent improvement in diagnostic and treatment methods, the overall survival of the disease is unfavorable. Several studies have been performed to assess factors influencing lymph node metastasis and prognosis. The aim of this study was to evaluate some clinical and pathological factors influencing lymph node metastasis in oral squamous cell carcinoma (SCC). Materials and Methods: In this retrospective study, 111 cases of oral SCC registered from 1991 to 2001 were retrieved from the archive of the Department of Pathology of Cancer Institute. Cases were divided into two groups based on the presence of lymph node metastasis. Patients’ pathological reports and medical records were reviewed and variables such as age, gender, occupation, disease duration, site and greatest diameter of tumor and histopathologic grade were compared between metastatic and non-metastatic groups. Data were analyzed using SPSS package and t, chi square, Mann-Whitney and Fisher’s exact test with pResults: Among the studied factors, patients’ gender (female), the disease duration (more than 12 months) and tumor size based on T1–T4 category were significantly related to lymph node metastasis. Other factors failed to show any correlation with lymph node metastasis. Conclusion: Based on the results of this study, women with large tumors lasting more than 12 months might be of greater risk for lymph node metastasis.