The study delves into the role of ion exchange membranes in microbial electrosynthesis (MES) for methane production. It contrasts the efficiency and stability of methane production in MES reactors equipped with cation exchange membranes (CEM-MES) and anion exchange membranes (AEM-MES). AEM-MES outperformed CEM-MES, producing 10.1 times more methane, with Methanobacterium as the dominant microbe. Despite higher pH imbalances in AEM-MES, methane production was primarily linked to H2 production rates rather than pH levels. The microbial community composition in the cathode biofilm was significantly influenced by the membrane type. The findings highlight the importance of ion transport mechanisms in shaping microbial dynamics and the overall performance of MES systems. This research offers valuable insights into optimizing methane production in microbial electrosynthesis for sustainable energy generation and environmental conservation efforts.