Abstract: Lignin-based carbon fibers not only broaden the application fields of industrial lignin residues, but also reduce the manufacturing cost of chemical carbon fibers. In order to better prepare lignin-based carbon fibers with high mechanical properties, the research results of lignin-based carbon fibers in China and other countries are summarized in this paper. The formation mechanism, preparation method and microstructure of high mechanical properties carbon fibers were analyzed and summarized. Then, the types of intermolecular bonding, aggregation, surface micropore and fiber diameter which affect the mechanical properties of carbon fibers are summarized. It can provide reference for the study of preparation and mechanism formation of high performance lignin-based carbon fibers.