Based on microalgae biological treatment technology, the microalgae-bacteria symbiosis system can not only efficiently realize sewage recycling, but also utilize the interactions between microalgae and bacteria to enhance the pollutant removal capacity of the treatment system and recover synthetic biomass. Bacterial-algal symbiotic systems can also be coupled with CO_2 fixation, and the combination of high CO_2 concentration in industrial flue gas for microalgae cultivation can simultaneously achieve carbon reduction and reduce the energy consumption of additional aeration of microalgae to supplement CO_2, which is in line with the development needs of "carbon neutral" . This article presents a systematic introduction of the mechanism, interaction forms and influencing factors of bacterial-algal symbiotic system in wastewater treatment and resource recovery process, and a summary of the potential of bacterial-algal engineering in pollutant degradation, CO_2 fixation and recovery of microalgal biomass products. The study of nutrient exchange, information transfer and genetic adaptation between bacteria and algae reveales that the selection of suitable symbiotic bacteria and algae combination culture can effectively enhance the pollutant removal and CO_2 fixation efficiency in wastewater. The effect of symbiosis on the accumulation of biological components (protein, lipid, carbohydrate, etc.) of algae is enhanced and selective. The selection of algae species and corresponding symbiotic bacteria, the adjustment of inoculation ratio and culture conditions can improve the efficiency of industrial scale harvesting of microalgae and further processing of biofuel and medical health food products. Bacterial-algal symbiosis is coupled with wastewater treatment, CO_2 fixation and biomass energy recovery in one. This article presents a critical review of development and progress of wastewater treatment and resource recovery surrounding microalgae-bacteria consortia. The development of the synthetic multi-functional system based on the consortium facilitates building an integrated sewage treatment and resource recovery processing mode featuring in low-carbon, economical and sustainable.