In this paper we explored the use of an electrochemical quartz crystal microbalance (QCM) to follow the development of electrochemically active biofilms on electrodes. With this technique it should be possible to monitor simultaneously the increase in biomass and the current generated by the electrogenic bacteria in the biofilm. We monitored the adsorption and the subsequent growth of bacteria that are used in microbial electrolysis cells, on a gold electrode (anode). After attachment it took about 3 h for the bacteria to start to grow and develop a biofilm. Although the current was still relatively low, there is a clear correlation with the increase in biomass. The method is promising for the further investigation of the development of biofilms on electrodes (bioelectrodes).