Ingrown nail is a common disease in surgical clinics, especially in the first toe, and the condition is recurrent. The common view is that wearing shoes too tightly leads to pressure on the toe, or improperly trimming the nail leaves a sharp angle to pierce the soft tissue and cause infection, followed by granulation tissue proliferation. According to our clinical observation, the root cause of ingrown nails is the relationship between the size and shape of the nail body and the nail contour. If the nail body is too wide in relation to the nail contour (originally developed or caused by extrusion), or if the nail body is curled at an angle, which damages the nail contour, thus causing local inflammation and infection, recurring and forming ingrown nails. In the past, treatment by simple nail extraction had a high recurrence rate and often caused great pain to patients. To completely cure ingrown nails, we must resolve the conflict between the nail body and the nail contour, rather than just eliminating the inflammatory infected granules and soft tissues. In continuous clinical practice, we have developed a set of “partial excision of the nail bed + nail contouring” surgery. This procedure focuses on removing the redundant nail body and nail bed while reconstructing the relationship between the nail bed and the nail contour, thus making the nail groove flat and wide and less prone to recurrence. In addition, since this surgery is more traumatic than simple nail removal and is often infectious, preoperative cleaning and strict disinfection, postoperative anti-infection treatment and proper care and medication changes are the keys to ensure successful surgery and one-stage healing.