Nail bulging may be related to onychomycosis, malnutrition, congenital heart disease, etc., and should be analyzed according to the symptoms. 1. Onychomycosis: fungal invasion of the nail plate or under the nail can lead to onychomycosis, which can appear nail plate hypertrophy, uneven surface and other symptoms. 2. Hypertrophic osteoarthropathy: Hypertrophic osteoarthropathy is often accompanied by hypertrophy of the end joints of the fingers in the shape of a drumstick, thickening of the nail plate, nail bulging and other symptoms. 3. Congenital heart disease: Most of the congenital heart diseases do not have specific symptoms, which will cause patients with insufficient blood and oxygen supply, increased heart burden and other problems, and the phenomenon of nail bulging can occur. Nail bulging may also have other reasons, it is recommended to consult a doctor in time to clarify the cause of the disease, under the guidance of the doctor for standardized treatment, so as not to delay the condition.