The study of fungi resistance to heavy metals is a very important part in the bioremediation. In this paper we report the Mn resistance and hyperaccumulation in Cordyceps kyusyuensis in terms of mycelia biomass, manganese content in mycelia, antioxidant enzyme activities, peroxidation level, cation exchange capacity (CEC) of mycelia cells, and the distribution of manganese in cells in submerged culture supplemented with Mn²⁺ concentrations from 0 to 60 g/L. The results showed that the mycelia biomass of C. kyusyuensis was negatively correlated with manganese concentration, and the upper limit of Mn²⁺ concentration for mycelia growth was 60 g/L. At a Mn²⁺ concentration of 70 g/L or above, the mycelia growth was completely inhibited. The manganese content in mycelia increased significantly with the increase in Mn²⁺ concentration in the culture medium when the Mn²⁺ concentration in the culture medium was below 60 g/L, up to 1.0013% manganese content based on the dry weight of mycelia was approached when the manganese concentration in the culture medium was 10 g/L. The contents of malondialdehyde (MDA), soluble protein (SP) and soluble sugar in mycelia of C.kyusyuensis were negatively correlated with the Mn concentration in the culture media, which were significantly different between the control and the group treated with manganese in the culture medium. The activity of antioxidant enzymes including peroxidase (POD), catalase (CAT) and superoxide dismutase (SOD) in mycelia of C. kyusyuensis all increased with the increase in the initial Mn concentration in the culture media, but the mode of change in those indices varied greatly. The manganese content in the insoluble components (91.51%-98.6%) were much higher than that (1.4%-8.49%) in the soluble part of the mycelia cells. The cation exchange capacity (CEC) in C. kyusyuensis mycelia did not show significant change with the increase in Mn concentration in the media. The cell wall, cell membrane and organelles of C. kyusyuensis played major roles in binding the manganese ions in manganese accumulation, while the soluble components in cytoplasm played a minor role. Under manganese stress, the joint action of antioxidant enzyme in removing the great amount of free radicals due to peroxidation and maintaining the normal metabolism of cells is important in the mechanisms of manganese resistance in C.kyusyuensis. Compared with other fungi, the resistance to manganese stress in C. kyusyuensis is relatively high with a threshold of 60 g/L, and its ability to hyperaccumulate manganese is also very high. Our experiments showed that the manganese accumulated in the mycelia on dry weight basis was 1.0013%, just approached 1%, the threshold of hyperaccumulation, this makes the macrofungi C. kyusyuensis a potential hyperaccumulator for manganese. The high resistance to manganese stress and the high ability to accumulate manganese under submerged culture suggest that C. kyusyuensis may be applied to the bioremediation of contaminated water and soil. On the other hand, manganese content in the mycelia should be monitored and proven safe when C. kyusyuensis is used for medical purposes due to the ability to hyperaccumulate manganese in this fungus.