Nail deformation and bumpiness may be caused by onychomycosis, psoriasis, malnutrition, trauma and so on. 1. Ringworm of the nail: its cause is mostly related to the invasion of the nail plate by fungi such as Trichophyton rubrum, Candida, and Trichophyton mustelii, and the nail plate of the patient will appear cloudy, thickened, and the surface is uneven and other symptoms. 2. Psoriasis: when psoriasis involves nails, there will be thimble-like depression, which will also be manifested as uneven nail deformation. 3. Malnutrition: Mostly seen in children, it is related to partiality and picky eating, such as lack of calcium, iron, vitamins and other nutrients, which can also lead to nail deformation and unevenness. 4. Trauma: it means that the nail is damaged by the nail plate or nail bed after being subjected to violence, which may cause the nail to be deformed and bumpy. There may be other causes of deformed and bumpy nails, so patients are advised to consult a doctor for examination and clarification of the causes.