Lymphedema is caused by the absence or obstruction of lymphatic vessels, the obstruction of lymphatic fluid return, and the accumulation of large amount of body fluids and proteins under the skin. Mastectomy causes local lymphatic system damage due to removal of surrounding lymphatic tissues, and the effect of postoperative radiation therapy, wound infection and mid- and long-term postoperative scar contracture make lymphedema one of the common unavoidable complications after breast cancer surgery. The upper limb edema after breast cancer surgery is mainly caused by the obstruction of lymphatic return after axillary lymph node removal. Clinically, it manifests as different degrees of swelling and pain in the affected upper limbs from the upper arm to the forearm and even the hand. If there is a small local wound, the edematous upper extremity with low local resistance can easily be infected and cause acute lymphangitis, commonly known as “fire flow”. The patient’s upper extremity skin is red, painful, and painful, with a dermatitis-like appearance, and in severe cases, a generalized fever, which requires antibacterial medication to improve. Recurrent attacks will aggravate upper limb edema.