The “Mesogen-Jacketed” liquid crystal polymers (MJLCPs) simultaneously show the structures of side-chain liquid crystal polymers and the properties of main-chain liquid crystal polymer, which exhibit different ordered structure, excellent structure ability and physical property. The performances make them widely application in functional materials. This work summarizes the latest developments in the design and synthesis of MJLCPs as functional materials in recent years as well as the relationship between structures and performances, including high-temperature thermoplastic elastomers, polymer electrolytes, photoluminescent liquid crystal, polymer electroluminescence, and polymer solar cells, and the prospect of their further development is also given.