Abstract: Objective: To reveal the relationship between the expression and tumor behavior, such as invasion and metastasis in tongue squamous cell carcinoma (TSCC), by analyzing expression of the urokinase-type plasminogen (uPA) and nm23-H1. Methods: The expression of uPA and nm23-H1 at protein level was examined in 74 cases of TSCC using strep avidin-bi-otin complex (SABC) immunohistochemical technique. Results: The expression of uPA and nm-23 H1 showed a negative correlation with tumor pathological grade. The expression of uPA was positively related to cervical lymph-node metastasis. The expression of nm23-H1 was negatively related to cervical lymph-node metastasis. The expression of uPA had a negative correlation with the expression of nm23-H1. The TSCC cases with uPA(+)/nm23-H1 (-) revealed a significant higher tendency of cervical lymph-node metastasis compared to the uPA(-)/nm23-H1(+) group. Conclusions: The results obtained indicate that uPA and nm23-H1 protein may be an important biological marker in invasion and lymph-node metastasis of the TSCC.