Knife scars can be removed by medication, laser and surgery. 1. Medication: Steroid medication such as Triamcinolone acetonide can be injected into the scar, which can inhibit the continued growth of the scar, and also soften and minimize the scar. 2. Laser: common lasers include carbon dioxide laser and erbium laser. Erbium laser can vaporize and exfoliate hyperplastic keloid scars and directly improve the appearance of keloid scars. Both types of lasers can promote collagen rearrangement of the skin to improve the appearance of keloid scars. 3. Surgery: The purpose of plastic surgery to treat scarring is to remove the obvious scar tissue and try not to leave obvious traces. Postoperative drugs such as silicone gel can also be used externally to inhibit scar proliferation and pigmentation and promote scar softening. Surgery is an invasive treatment that still carries the risk of causing scarring and requires caution. Knife scars can also be removed by compression therapy, silicone film pressure paste method, ultrasound therapy, etc. If knife scars affect the aesthetics and life, it is recommended to go to a regular hospital for treatment if the patient has a need for treatment.