Compared with a microbial fuel cell (MFC) of single flora, the MFC of mixed flora provide much better denitrification and electricity generation performance. Therefore, in-depth analysis of the kinetic features such as the structures of various types of microflora in MFCs is of important theoretical and practical significance. There is little existing research on the electricity generation and pollutant removal process of cathode microorganisms and the functions of microbial flora. To this end, this paper constructs an MFC anaerobic-aerobic coupled denitrification system and studies its performance enhancement method. First, the basic principle of MFC biological denitrification was expounded, the kinetics was introduced into the analysis of the reaction between the MFC microorganisms and pollutants, and the migration and transformation occurring in the reaction process and the mechanism of transformation speed changes were revealed. Then, the analysis and calculation methods for the electrochemical parameters and microbial diversity index in MFC were explained in detail, and the experimental results and analysis conclusions were given.