The aim of this study is to investigate the expression of matrix metalloproteinase 2 (MMP-2) and the tissue inhibitor of metalloproteinase 2 (TIMP-2) in oral squamous cell carcinoma (OSCC) and adjacent normal tissues, and explore the role of MMP-2 and TIMP-2 in carcinoma metastasis and invasion. Expression of MMP-2 and TIMP-2 was evaluated in 40 cases with semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemical techniques. The values of MMP-2/beta-actin and TIMP-2/beta-actin in OSCC were significantly higher than those in adjacent normal tissues 2 cm and > or = 5 cm from carcinoma tissues (p<0.05). The results of immunohistochemical analysis show that the positive expression of MMP-2 and TIMP-2 protein in tumor tissues (60.0 and 52.5%) was higher than that in adjacent normal tissues 2 cm (30.0 and 22.5%) and 5 cm (22.5 and 25.0%) from cancer tissues, and the difference was significant p<0.05). The expression of MMP-2 and TIMP-2 was related to the differentiation degree of tumor cells, metastatic lymph node status and stage of carcinoma, but not related to the age and gender of patients, or location of the carcinoma. Therefore, MMP-2 and TIMP-2 may play important roles in the invasion and metastasis of OSCC.