Nail fungal disease refers to lesions caused by dermatophytes, yeasts, and non-dermatophytic molds that invade the nail plate and/or nail bed, and is a source of superficial fungal infection, of which lesions caused by dermatophytes are called onychomycosis. Groups such as nail trauma, diabetes, immune deficiency, malnutrition, and the elderly are the most prevalent groups for nail fungal disease; young women with nail care habits are susceptible. Clinical manifestations of nail fungal disease: nail fungal disease generally has no conscious symptoms, but pain and itching can occur when combined with nail fungus. The nail may change in color, shape and texture. Such as nail thickening, deformation, small concave, loss of luster, sometimes into a “hook” shape, sometimes can become a “trumpet” shape. The most common color is grayish yellow, which is also the origin of the term “gray nail”, but it can also be yellow, red, white, or green. The fungus is invaded by the distal nail and travels along the distal nail bed to the nail plate. The nail plate becomes cloudy, discolored, and thickened, and keratinous growth under the nail bed leads to the accumulation of debris under the nail. The lesion starts at the distal end of the nail and gradually progresses to the proximal end. 2, proximal nail under the nail: fungal disease causing fungi from the proximal invasion, from the root of the nail to the distal growth. It often manifests as uneven and thickened proximal nail plate, sometimes with color change. This type often occurs in immunocompromised patients. 3, superficial white nail type: nail fungus disease causing fungi from the surface of the nail plate invasion, often forming white islands of damage, serious to the whole nail plate white, surface loss of luster, scaling and other changes. 4, the whole nail destruction type: the above-mentioned types of nail fungal disease without treatment, can eventually develop into the destruction of the whole nail. Intra-nail type nail fungal disease refers to the infection inside the nail plate caused by the fungus. Clinically the invaded nail plate is diffuse color, texture, etc., such as creamy white, greenish gray, the surface of the nail plate without keratinization performance.