Objective: To investigate the possible correlation between osteoglycin expression and gelatinases activity of tumor cells.Methods: Eukaryotic expression plasmid and antisense expression plasmid of osteoglycin were constructed, and transfected into mouse hepatocarcinoma Hca-F cells and Hca-P cells, respectively. RT-PCR and Western blot were employed to analyze osteoglycin expression in tumor cells. Zymographic analysis was used to observe the possible correlation between osteoglycin expression and gelatinases activity of tumor cells cultured under different conditions. Results: High expression of osteoglycin after transfection of osteoglycin gene attenuated secretion of gelatinases in Hca-F cells cultured with extract of lymph node (P