A large amount of threonine mother liquor is produced during the production of threonine by fermentation,in which many impurities are intermingled,e.g,threonine,other amino acids,residual sugars and inorganic salts.The main amino acids in the fermentation mother liquor are threonine and glutamic acid.Bipolar membrane electrodialysis (BMED) was used to separate threonine and glutamic acid in order to avoid the waste of resources.Firstly,three types of membrane stack (BP-C-BP,BP-A-C-BP,BP-A-BP) configurations are investigated,and the configuration stack BP-A-BP is considered the most suitable for separation of the mixed amino acids.Then the effects of operation voltage on separation efficiency,energy consumption and current efficiency were examined.Results indicated that 50V is the most appropriate operation voltage.The energy consumption is 11.04 kW h/kg,current efficiency is 82.6%,and the purity of the glutamic acids in recovery compartment is as high as 97.5%.Besides,strong acid type 001×7 cation-exchange resin is added into the glutamic acid recovery compartment to reduce the energy consumption.Thereby,a lower energy consumption 6.33 kW h/kg could be achieved.Hence,the BMED process to separate the mixed amino acids containing threonine and glutamic acids is feasible.