With the development of microsurgery technology, its application is more and more extensive. Besides ophthalmology, otorhinolaryngology and neurosurgery, microsurgery also plays an important role in replantation, transplantation and reconstruction: ① replantation of severed limbs (fingers) is an important part of clinical application of microsurgery; ② Tissue transplantation with vascular anastomosis: it is the most widely used field in microsurgery, including transplantation of vascular flap, musculocutaneous flap, bone and periosteum, omentum, toe and jejunum, and muscle transplantation with vascular nerve, which is used to repair large areas of soft tissue, bone and muscle defects, reconstruct thumb and reconstruct esophagus. ③ Microrepair of peripheral nerve can make the outer nerve membrane and nerve bundle more accurate and improve the surgical effect, and vascular nerve transplantation can repair the long nerve defect; ④ Applying microsurgical technique to anastomose the distal lymphatic vessel with the adjacent vein, so that the lymph can flow directly into the vein, which has a good effect on eliminating edema, controlling infection and improving chyluria; ⑤ Small organ transplantation with vascular anastomosis provides an animal model for allogeneic organ transplantation, and is also used for testicular and ovarian transplantation in clinic. ⑥ Small tube microsurgery, such as vasectomy and tubal anastomosis, can improve the patency rate.