Fed-batch cultures were performed to improve the productivity of erythritol. When only glucose was added to the culture broth, the specific erythritol production rate was markedly decreased from 0.042 g/g/h to 0.023 g/g/h. On addition of both glucose and corn steep liquor, the rate was kept almost constant at 0.042 g/g/h throughout the fed-batch fermentation period. The repeated fed-batch culture method showed a maximum erythritol productivity of 1.86 g/l/h and a 45% of total erythritol conversion yield, corresponding to a 23% and 15% increase compared with batch fermentation.866577580