It is proved that the effect of tannin concentration on the mycelial growth of fungi. Auricularia cornea (white strain) were treated with different concentrations of tannins in petri-dishes and liquid shaking flasks. The growth rate of mycelium, the ratio of clamp connection, morphology of mycelium, biomass of mycelium and activity of antioxidant enzymes were determined. The results showed that different concentrations of tannin significantly decreased the rate of mycelium. However hign concentration of tannin stress increased the content of thiobarbituric acid in mycelia and had obvious time and concentration effects. Different antioxidant enzyme activities also had different responses to tannin stress. It provides theoretical basis for fungi to utilize and develop substrates containing tannin such as pine.