Patients with ingrown nail onychomycosis are often encountered in clinical clinics with painful red toes and recurrent episodes that affect walking. So what is an ingrown nail? In layman’s terms, it means that the toenail has grown into the flesh. The main cause of ingrown toenails is due to poor toenail trimming habits, as shown in the figure. The red area is the actual area of the toenail; the blue area is the area of the nail seen by the naked eye Figure 2. The wrong way to trim the nail: only the shaded part of the toenail is cut Figure 3. For the redness and swelling that has developed, anti-inflammatory support is also needed, including topical creams and drops. If an abscess forms it also needs to be treated with an incision to drain the pus and a change of medication. Finally, in order to avoid ingrown nail infections, we would like to advise parents: 1, do not cut the toenail too short or too deep, just keep 1-2mm. 2, do not wear tight pointed shoes to avoid squeezing the toes. 3, to protect our toes to avoid kicking, bruising; 4, timely correction of toenail deformities.