With ultra short pulse width and high peak power, femtosecond laser plays an important role in micro/nano machining. However, the processing efficiency of femtosecond laser restricts its application in industry. In recent years, researchers have successfully applied spatial light modulator to femtosecond laser processing to further improve the efficiency and flexibility of femtosecond laser processing. In this paper, the progress of recent research of Si-based liquid crystal spatial light modulator in femtosecond laser processing is reviewed. It concludes three processing methods that is multi foci parallel processing, structured light field parallel processing, and vector light field processing. The advantages and disadvantages of these processing methods are analyzed. The recent study of the field quality is discussed in the aspects of the uniformity and diffraction efficiency of the field. Finally, the problems in this field are discussed, and the prospect for the future is put forward.