Femtosecond laser has been an important processing technique for micro/nano structures in recent years. It can modify and ablate materials, and is capable of machining high-precision three-dimensional structures in specific areas. Femtosecond laser machining has broad application prospects in micro/nano processing. In this paper, the general interaction process between femtosecond laser and metals is described, and the methods for the preparation of micro/nano structures are introduced, such as femtosecond laser direct writing, femtosecond laser induced surface periodic structure, and femtosecond laser composite chemistry method. Then, the applications of femtosecond laser for the preparation of micro/nano structures on metal surfaces in environmental engineering, aerospace, and biomedicine are discussed. Finally, the shortcomings and future research directions of preparation of micro/nano structures by femtosecond laser are summarized and prospected.