Electrochemical impedance spectroscopy (EIS)is a sensitive indicator of a wide variety of chemical and physical properties. Au increasing trend towards the develoment of impedimettric biosensors is being curremtly observed. Impedimetric techniques have been performed to characterixe the fabrication of the biosensors and to monitor the catalyzed reactions of enzymes or the biomolecula recognition events of specific binding proteins, lectins, reeptors, nucleic acids, whole cells, antibodies or antibody-related substances. However, little attention has beenpaid to reviewing this interesting research area. Herein, impedimetric biosensors are reviewed and many novel designs are discussed.