Microbial desalination cells (MDCs) are an emerging green and sustainable energy recycling technology, which utilize microbial extracellular respiration to simultaneously drive salinity removal, electricity generation and degradation organic pollutants. Firstly, the energy consumption and limitations of conventional energy-intensive desalination techniques (thermal and membrane processes) are summarized. Secondly, the MDCs was systematically analyzed from the aspects of work mechanism, configuration evolution, operative parameters and microbial community of the classic MDC system. The collaborative efficient treatment of wastewater by multiple MDC coupled technologies and its challenges for sustainable development are described in detail. Finally, the future strategies are prospected from the perspective of MDCs in efficient, sustainable and low-carbon wastewater treatment, saltwater desalination and energy/resource recovery.