Laser direct deposition technology can be used for producing large metal parts due to its unlimited capacity for manufacturing size and high material freedom. However, conventional laser direct deposition technology makes it challenging to consider both printing efficiency and printing quality, thereby restricting the popularization and application of this technology. Therefore, high-speed laser direct deposition technology has gained research popularity. In this paper, the effects of scanning speed and laser power on the process characteristics of Inconel 718 laser direct deposition are discussed, and the changes in surface morphology, microstructure characteristics, internal defects, and mechanical properties of conventional and high-speed laser direct deposition are analyzed. Finally, the challenges of applying high-speed laser direct deposition technology in three-dimensional additive manufacturing are discussed, which offers guidance for the development of high-speed laser direct deposition technology in the future.