Due to the advantages of good transparency, excellent mechanical properties, biodegradation,etc., semi-crystalline polylactic acid (PLA) shows a wide range of application and other characteristics during processing. Therefore, the work aims to summarize the research and application and latest progress of PLA-based composites in 3D printing technology to provide reference. Focusing on fused deposition molding (FDM) and PLA matrix and based on reviewing recent literature at home and broad, the structure property of PLA, 3D printing process, modification of PLA matrix composites and other aspects were discussed, with emphasis on the technical optimization of process parameters and the latest research progress of structural modification of composites. Research on preparation of PLA-based composites by FDM has achieved fruitful results, showing excellent performance in the 3D printing industry with great potential and increasing commercialization degree. Cheap, efficient and customizable 3D printing is widely concerned and favored by researchers at home and abroad. With the continuous exploration and breakthrough of new technologies, and the application of new materials such as nano-materials and new polymer materials, 3D printing will have absolute advantages in molding technology.