The mushroom Lentinus lepideus was used to produce mycelial as well as soluble polysaccharides in bioreactor cultures. To determine optimal submerged culture conditions, both growth characteristics and water soluble polysaccharides production were compared among four different types of bioreactor and culture conditions. For the production of mycelial biomass, the following bioreactors were proven to be effective in decreasing order: an external-loop type air-lift bioreactor (ETAB; 7 g/l), a balloon type air bubble bioreactor (BTBB; 6.2 g/l), a stirrer type bioreactor (STB; 6 g/l), and a column type air bubble bioreactor (CTBB; 5 g/l). Maximal production of water soluble exopolysaccharides (EPS; 0.62 g/l) and endopolysaccharides (PPS; 7.7%) could also be obtained from BTBB. The mycelial biomass increased with increase in glucose concentration from 15 g/l to 75 g/l in the media. In contrast, PPS contents in the cells decreased with increase in glucose concentration in the media, showing the highest PPS content (7%) at 15 g/l. Among different medium feeding types, fed-batch culture based on concentration control in media (10 g/l) produced higher mycelia than fed-batch culture based on volume control of media (5.8 g/l) or batch culture (3.4 g/l). EPS production was also higher in fed-batch culture based on medium concentration control than that in other feeding types.