Ultrafast lasers have the characteristics of high pulse energy, high processing accuracy, and small heat affected zone. They have unique advantages in material processing, especially in the fields of micro-nano processing and surface modification. This paper introduces the typical numerical simulation methods of ultrafast laser processing metal materials. It summarizes the research progress of numerical simulation based on the three mechanisms of ablation, plasma effect, and periodic surface structure formation in recent years. Several models and limitations of these mechanisms are introduced, the current challenges of numerical simulation for ultrafast laser processing are summarized, and future research focuses are prospected.