A hard thing growing inside the finger hurts when pressed, which may be caused by periungual warts, onychomycosis and tenosynovitis. 1. Periungual warts: wart-like plaques and pimples will appear on the patient’s periungual or nail bed, and some patients will have pressure pain and tenderness. The cause of the disease is mostly related to HPV infection of the nail. 2. Trenchitis: mainly manifested as redness, swelling and pain in the peri-nail tissues, and some patients will have abscesses under the nail. Its causes are mostly related to trauma, bacterial infection and exposure to mutagens. 3. Tenosynovitis: usually manifested as localized pain, pressure pain and other symptoms, mostly in the fingers, shoulders and other places, there will be painful nodules. The cause of a hard thing inside the finger pain is not the same, we recommend that patients seek medical examination to determine the cause of the disease.