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