Gray nails, or nail fungus, can lead to nail loss when the fungal infection of the nail plate and nail bed progresses to the final stage and the nail plate is destroyed. Nail fungal disease refers to the fungal infection (e.g., Trichophyton rubrum, Trichophyton mustelii, or yeasts, molds, etc.) that occurs in the nail plate and the subnail tissues, and is most often due to the direct transmission of tinea versicolor. Due to the different degrees of fungal invasion of the nail, it can be categorized as superficial white, distal lateral subnail, proximal subnail, and total nail disfigurement. The total nail destruction type is the final result of nail fungal disease, there will be the destruction of the entire nail plate, the nail plate is gray-yellow or gray-brown, the nail plate can be completely or partially detached, and the nail bed residual accumulation. Gray nails, it is recommended to consult a doctor in time, follow the doctor’s instructions for treatment, adhere to the medication in order to facilitate healing.