The dynamic multi-frequency bioimpedance measuring system based on discrete fourier transform is designed in this paper, in order to obtain the bioimpedance information in different frequencies simultaneously. A novel information extraction method of discrete fourier transform combined with the virtual reference point is presented. The hardware platform of the system is composed of the signal source module, the signal conditioner and PCI-6111 card. Using LabVIEW, functions of the collection, analysis, display and data storage are implemented, with which the bioimpedance information can be detected dynamically. From the experimental results, the dynamic reaction of respiratory and sphygmous information in different frequencies can be manifested according to the human impedance measurement