With the rapid development of industrial technology and the extensive use of fossil energy, the CO2 emissions are increasing year by year, and the global warming it causes is one of the most concerned topics in the global environment and economy. CO2 capture, utilization and storage (CCUS) is a key technology for China to achieve the goal of carbon peaking and carbon neutrality, which is of great significance for China to reduce CO2 emissions and build ecological civilization. Microalgae have the advantages of fast growth rate, strong adaptability to extreme environments, and low production costs. Its mediated CCUS technology is able to absorb and fix CO2 and convert it into high value-added products. In this process, the species of microalgae play a crucial role in determining CO2 fixation efficiency and biomass production. At present, many review studies focus on the use of microalgae for carbon capture, utilization and storage, but there are few reviews on the latest strategies to improve the carbon capture efficiency of microalgae. Based on the development status of microalgae carbon fixation technology, the photosynthesis and carbon fixation mechanism in microalgae were systematically discussed. Then, this work reviewed recent advances in microalgal strains for CO2 fixation, focusing on the improvement and modification of strains used in coal-fired flue gas. A further comprehensive summary of recent trends and strategies to improve photosynthetic efficiency in microalgae was presented. Several strategies to modify and improve microalgal strains, including random mutagenesis, adaptive laboratory evolution, and genetic engineering, can be used to generate the desirable microalgae strain. Among them, genetic engineering can not only truncate the antenna size of the light-harvesting complex (LHC) to improve photosynthetic efficiency, but also improve the velocity and selectivity of Rubisco. Strategies to intervene by adding nanomaterials (NMs) to microalgal cultures can enhance CO2 diffusion/dissolution in solution, significantly increase the relative electron transport rate in photosynthetic system Ⅱ(PSII) as well as reactive oxygen species(ROS) levels in microalgae, thereby improving the general response to carotenoids photosynthesis. Finally, the current challenges and future development directions of this technology were clarified, and a high-efficiency microalgae carbon sequestration system that tolerates flue gas should continue to be developed. Finally, the current challenges and future development direction of this technology were clarified. Efficient microalgae carbon fixation systems  should be researched and developd that can tolerate flue gas.