This paper summarizes the working principles of all-fiber mode converters such as mode selective couplers and acoustically-induced fiber gratings. Combining the advantages of a mode-locked fiber laser and mode converters is a simple and effective method to generate ultrafast vector beams and optical vortex beams. The generated ultrafast laser with high-order modes (HOMs) has high peak powers and high mode purity. The experimental results demonstrate that the fast response and broadband mode conversion characteristics of these mode converters. In addition, the future development directions and application prospects of ultrafast HOMs are discussed.