Gelatinases, matrix metalloproteinase-2 (MMP-2) and MMP-9 have been implicated in tumor invasion and metastasis, although their regulations are still unclear. Objective: To determine the effect of cytokines on gelatinase activities and invasion of pharyngeal cancer cells. Methods: A pair of tumor cell lines derived from pharyngeal lesions (HN30) and metastatic cervical lymph nodes (HN31) were used in this study. The tumor cells were treated with IL-α, IL-1β, IL-6, TNF-α, TGF-β or HGF (1ng/ml) for 24 h. Conditioned media were harvested and gelatinolytic activity was determined by zymography. Cytokine-mediated invasion of the tumor cells was assayed using a modified Boyden chemotaxis chamber. Invasive cells were counted after incubation with cytokines at a concentration of 1 ng/ml for 5 h. Results: IL-α, IL-1β, IL-6, TNF-α, TGF-β and HGF stimulated MMP-2 activities of HN30 to 1.4-,2.3-,1.8-,1.1-,1.7- and 1.1-fold that of the untreated cells, respectively ( ANOVA, p<0.05). The production of MMP-2 in HN31 treated with IL-α, IL-1β, IL-6, TNF-α, TGF-β and HGF was shown to 5.2-, 4.6-, 4.9-, 2.2-, 3.1- and 2.1-fold, respectively, those in controls (p<0.05). IL-α, IL-1β, IL-6, TNF-α, TGF-β and HGF stimulated MMP-9 production in HN30 by 4.7-, 5.6-, 1.0-, 4.8-, 5.1- and 3.3-fold, respectively whereas activities of the enzyme in HN31 were enhanced to 6.3-, 13.5-, 1.0-, 1.1-, 1.7- and 1.0- fold, respectively (p<0.05). The invasion of HN30 treated with IL-α, IL-1β, IL-6, TNF-α, TGF-β and HGF was shown to 1.3-,1.0-,1.5-,1.4-,1.3- and 1.2-fold, respectively, those in controls (p<0.05). Treatment of IL-α, IL-1β, IL-6, TNF-α, TGF-β and HGF increased the invasion of HN31 to 1.5-,1.2-,3.0-,3.2-,3.6- and 1.5-fold, respectively (p<0.05) Conclusions: The gelatinase production and invasion of pharyngeal cancer cells were influenced by cytokines. The enhancement of gelatinases and invasion were dramatically observed in metastatic cancer cells.