The antifungal effects of polyphosphates on growth of Candida albican and Trichophyton mentagrophytes were studied. The polyphosphates with chain length of 15, 45, and 75 were inhibitory to growth of fungi whereas no inhibition was shown by pyrophosphate. As chain length increase, the more inhibitory effect of the polyphosphates on fungal growth was observed. The concentration of polyphosphate at $800;{mu}g/ml$ completely inhibited the growth of fungus. Supplementation of the medium with $Mg^{2+};and;Ca^{2+}$ reduced inhibitory effect of polyphosphate on growth of C. albican treatment of C. albican with polyphosphate, the release of nucleic acid out of cell was observed. When C. albican exposed to polyphosphate were examined, profound changes of cell morphology such as cell swelling and surface blebs were observed. In addition, propidium iodide, membrane impermeable dye, stained the nucleus of C. albican cell treated with polyphosphate. Therefore, it is proposed that the antifungal activity of polyphosphate might be related with its chelation effect to essential cation components of fungal cell wall or membrane.